4. An Introduction To Newton’s Laws of Motion

Basing his work on much of Galileo’s pioneering physics and mathematics, Newton made perhaps the largest of all contribution to mechanics. Newton proposed a scientifically sound explanation of why objects fall downward

To start off this section, there are some keynotes to be made about the use of the word ‘acceleration’ in physics. Velocity is a vector measurement, meaning that velocity has both a magnitude and direction. Speed, however, does not have a direction and only has a magnitude; hence speed is a scalar measurement.

To put this simply, speed is how fast an object is moving in an arbitrary direction whilst velocity is how fast an object is traveling in a set or linear direction. If an object is traveling at a constant speed, but is traveling in a circular, zigzagging or sinusoidal path, the velocity is constantly changing direction; hence there is a change in velocity.

Acceleration is a measurement of change in velocity over time. This means that if a body is traveling at a constant speed, but again in a circular, zigzagging or sinusoidal path then the body is accelerating.

To say an object is decelerating is not strictly wrong in physics, though the term ‘deceleration’ is none-standard. When writing an equation, it would be impractical to have a different symbol for both acceleration and deceleration, so if an object appears to be decelerating then it is often referred to as accelerating by a negative magnitude. For instance, instead of accelerating by 5 ms^-2 and then decelerating by 5 ms^-2, it would usually be said that a body was accelerating by 5 ms^-2 and then accelerating by -5 ms^-2.

Acceleration also uses derivatives, which is a mathematical process for the measurement of how a function – in this case, an objects velocity – changes as an input – in this instance, time – changes. Acceleration can be written as ∂v/∂t, which translates to ‘delta v’ divided by ‘delta t’, or ‘change in velocity over ‘change in time’. The symbol ‘∂’ is simply an abbreviation of the phrase ‘change in’.

This can be used in graph theory whereby if we plotted a graph of speed against time, the area under the graph would indicate total distance traveled and the gradient of the graph would indicate ‘∂v/∂t’, or ‘acceleration’. The gradient of the graph is a measurement in how y changes as x changes. See Figure 1 for more information.

Figure 1


Alternatively, differentiation can also be written as ∆v/∆t or f’(v) (whilst f(v) is shorthand for ‘a function of v’). These all, however, have the same meaning; in fact, ‘∆’ is simply the capitalised Greek alphabetical symbol of ‘∂’.

The mathematical implications of differentiation are not needed the following segment of this article, so can be dismissed for the time being. I will be tackling differentiation at a later date, along with graph theory, logarithms and integration.

So, let us now observe Newton’s three laws of gravitational attraction. Newton originally proposed that.

1. A body, at rest or traveling at a constant speed, has a resultant force of zero.

2. The relationship between a force and a mass is acceleration, and the acceleration acts in the direction of the force. This can be equated as F=ma.

3. For every action, there is an equal and opposite reaction.

So, let us analyse these rules. The first rule tells us that if an object is at rest, i.e. the object is not in motion; the force on the object is zero. Whilst an object is moving, if the velocity of the object is constant then there is no force on the object. This is analogous to when a bowling ball is rolled down a lane. As the bowling ball is swung, the ball accelerates from its resting position behind a persons back and a force is exerted on the ball during the initial swing in order to “push” the ball forwards. Once the ball has left the player’s hand, however, the ball no longer has any force acting on it, and it travels down the lane at a constant velocity. In order to speed up or slow down the velocity of the ball, external forces would need to be used, but for the ball to roll at a constant velocity, no force is required. In reality, there is a force of friction slowing down the ball, but this force is so small as to be considered negligible in practice. It would be safe to assume that in this instance, there is not force acting on the ball.

However, an object can experience a force whilst traveling at a constant velocity. Take a skydiver for example. As the skydiver jumps from a plane, a force of gravity pulls the skydiver downwards. Initially, the skydiver accelerates towards the earth, but as the skydiver falls, air pushes up against the skydiver in a process called air resistance. As the skydiver descends at a faster and faster rate, the air resistance increases. When the skydiver reaches a certain speed, the air resistance on the skydiver is so great that the skydiver stops accelerating and remains traveling at a constant velocity; this is called a terminal velocity.

At this velocity, there is still a force pulling the skydiver down to earth, but there is equal force acting in the opposite direction that is resisting the skydivers fall. This means that there are forces acting on the skydiver, but the resultant force (the sum of the two forces) amount to zero. This law was derived heavily from Galileo’s Law of Inertia.

Newton’s second law was perhaps his most famous and certainly has the biggest implications, allowing calculations and equation derivatives. We have already seen how Newton’s second law can be applied, but Newton’s second law also paved the way for much more advances in mechanics and motion, both directly and indirectly.

We can see how this law was derived using the first law. The first law shows us that a body must have an acceleration in order to have a force. This would lead us to assume that force ‘F’ is proportional to acceleration ‘a’, which is indeed the case. This proportionality is the body’s mass, ‘m’. To accommodate for air resistance, the equation can equally be written as F₁ - F₂ = ma, where F₁ is the pushing force, F₂ is the opposing resistance and F = F₁ - F₂. As you can see from this, if F₁ is equal to F₂ then F₁ - F₂ = 0. Hence the resultant force ‘F’ is zero, and so ma = 0. As the mass is constant, only ‘a’ can change, so ‘a’ must also be equal to zero, hence there is no acceleration.

Newton’s third law tells us that for every action, there is an equal and opposite reaction. This essentially means that, if you push an object, the object you push “pushes back” against you. This is what resistance essentially is, an opposing force.

One way to consider this law is through gravity. Whilst you are standing on the earth, you are being pulled down and hence exerting a force on the earths surface. According to Newton’s third law, the earth must also be exerting a force upwards on you. This force is called the Normal Contact force, often written as a stylised R symbol.

As earlier mentioned, mass and weight are entirely different. Mass denotes the amount of a substance, whilst weight is the force of that mass from gravity. Taking the average adult male to be about 75 kg in mass, we could use the formula F=ma to work out the weight of an average human. However, whilst a person is not moving they are not accelerating, but we still have a weight otherwise we would float off into space. As with the skydiver traveling at terminal velocity, we do all have a force on us dragging us down, but there is a resistance that is repelling us, and the resultant force is zero.

Using this, we know we are accelerating downwards. This acceleration is caused by gravity, and is called – quite aptly – acceleration due to gravity. So, what is this acceleration’s value? There is not set value. Gravity changes depending on where you are, and your weight on the moon is about a tenth of your weight on earth, so to work out a person’s weight, we must first calculate the acceleration due to gravity.

On or close to the earths surface, the weight due to gravity is about 9.81 ms^-2 (meters per second squared). This tells us that the weight of an average adult male is equal to 75 kg multiplied by 9.81 ms^-2 which equals 736 Newtons, or kg m s^-2. But how do we know that this acceleration is about 9.81? To do that, further calculations must be made.

A simultaneous equation is simply the process of merging two separate equations using a common variable. Starting with Newton’s second law of gravity (F=ma) and Newton’s equation of gravitational attraction (F=GmM/r² we can deduce the following..

F=ma and F=MmG/r²

In this instance:

‘m’ is the mass of an average human,

And

‘M’ is the mass of the earth.

If F=ma and F=GmM/r², then

ma = GmM/r²

We can then divide each side by ‘m’ to cancel these digits out. Remember, when dealing with equations such as 2x=y, whatever you do to one side of the equation you must do equally to the other side. If we tripled y, we would have to also triple 2x to become 6x. If we divided each side by x, we would get 2=y/x. By dividing by ‘m’, we can get the following equation:

a = GM/r²

Where ‘a’ is the acceleration due to gravity, ‘G’ is the universal gravitational constant (6.67x10^-11); ‘M’ is the mass of the earth (in this instance at least) and ‘r’ is the distance between the two centers of mass.

The mass of the earth has been calculated to be approximately 6x10²⁴ kg and the radius of the earth is approximately 6,400,000 meters. As we are working from the center of the two masses and we are on the earth’s surface, the radius of the earth is approximately the equivalent of the distance between the two centers of mass, so this distance is used. Now we can continue with the calculations:

a = GM/r²

a = (6.67x10^-11)x(6x10²⁴) / (6.4x10⁶)²

a = 4.002x10¹⁴ / 4.096¹³

a = 9.7705 ms^-2

Which is remarkably close to the 9.81 ms^-2 as measured by Newton. It could also be noted that this example used approximate values and so will have a margin of error.

Using and rearranging the equations F=ma and F=GmM/r² allows other possibilities too and, by incorporating other simple equations, we could equally calculate the mass or radius of the earth for ourselves. The gravitational constant ‘G’ is much more difficult to accurately measure as gravity is a very weak force compared to other forces such as subatomic or electromagnetic forces. Wikipedia has the following to say on the measurements of the universal gravitational constant:

History of the measurement of G
The gravitational constant appears in Newton's law of universal gravitation, but it was not measured until 1798 — 71 years after Newton's death — by Henry Cavendish (Philosophical Transactions, 1798). Cavendish measured G implicitly, using a torsion balance invented by the geologist Rev. John Michell. He used a horizontal torsion beam with lead balls whose inertia (in relation to the torsion constant) he could tell by timing the beam's oscillation. Their faint attraction to other balls placed alongside the beam was detectable by the deflection it caused. However, it is worth mentioning that the aim of Cavendish was not to measure the gravitational constant but rather to measure the mass and density relative to water of the Earth through the precise knowledge of the gravitational interaction. The value that he calculated, in SI units, was 6.754x10⁻¹¹ m³ Kg⁻¹ s⁻².

The accuracy of the measured value of G has increased only modestly since the original experiment of Cavendish. G is quite difficult to measure, as gravity is much weaker than other fundamental forces, and an experimental apparatus cannot be separated from the gravitational influence of other bodies. Furthermore, gravity has no established relation to other fundamental forces, so it does not appear possible to measure it indirectly. Published values of G have varied rather broadly, and some recent measurements of high precision are, in fact, mutually exclusive.

Source: www.wikipedia.org

3. A Study of Basic Physics and Mathematics

Physics is a natural science, mostly concerned with matter and how matter interacts. The study of physics is very broad, and incorporates mainly Mechanics (Or “Newtonian” Physics) and Atomic Physics. Physics also incorporates Chemistry – with studies such as radioactive materials – and other branches of science, such as Astronomy or Engineering.

Perhaps the most basic form of Physics for many is Mechanics, often referred to "Newtonian" Physics after Sir Isaac Newton in honour of his contributions to the discipline.

Most physics relies closely on mathematics and so an understanding of advanced mathematics, particularly trigonometry, mechanics, algebra, logarithms, working with graphs and integration and differentiation are extremely important to physicists. In fact, almost all forms of mathematics can crop up in physics.

In mathematics, similar lines of data often have to be recorded written and this can tedious to write or translate. For this reason, mathematicians often use shorthand symbols to explain or illustrate an argument. These are important to understand; as without them equations can often appear meaningless. A key of symbols is recorded in this articles glossary.

To start this introduction to physics, a few basic mathematical rules will be examined: firstly, algebra. Algebra is one of the main branches of mathematics, and can range from very basic equations to large, complex structures. Algebra is the study of quantity and relationships usually between independent variables. Simple algebra is found in the following form.

Let x=3 and y=2 and 4x + 2y = z then z=16

We can prove this by replacing x and y with their variable sums. As x is equal to 3 and there are 4 lots of x, the sum of 4x is 12. As with y, the sum of 2y is 4. The product of 12 and 4 is 16, so z is 16. If we change the input variables x and y, our output, z, is changed by a proportional amount.

Algebra in physics works in the same way. In mechanics, an objects force is directly proportional to the mass of the object multiplied by the acceleration acting on the object. This tells use that Force (F) is directly equal to Mass (m) times Acceleration (a). Hence:

F=ma

As with the equations above, the equation F=ma relies on 2 input variables, mass and acceleration, and provides an output, the force of the object. Using this data, we can also re-arrange formulas to change an outcome. Let us use the formula F=ma again. If F is equal to mass times acceleration then Force divided by either mass or acceleration must be equal to both acceleration or mass respectively.

Hence if F=ma, a=F/m and m=F/a

Another important aspect of physics is the use of constants. We know, for example, that the diameter of a circle is directly proportional to the circle’s perimeter. This tells us that D is directly proportional to P. This proportionality is constant, so therefore r is directly equal to a constant multiplied by P. This constant is approximately 3.14172, but to save time, mathematicians simply write the symbol pi (π).

So we can alter the inputs so find the necessary outputs and use symbols to show direct proportionalities. To use a more complex example, let us use the equation for the gravitational attraction between 2 objects: mass M and mass m. The equation is as follows.

F=GmM/r² where G is a constant 0.0000000000667 *

*In practice, this is written as 6.67 x 10^-11

Or, more simply, the gravitational force between two objects (F) is proportional to the sum of the mass of the two objects divided by the distance (r) separating the two objects squared (Note: distance is measured from the centre of mass of each object). As you can see, writing F=GmM/r² is much quicker and simpler.

We can also rearrange this equation to find out other inputs. For example, to calculate r we could rearrange in the following way:

F=GmM/r²

F r²=GmM

r²=GmM/F

r=√GmM/F

So the radius r is equal to the square root of the sum of the two masses m and M multiplied by the universal gravitational constant G and divided by the force F.

AAn important aspect of physics that can be implemented in many situations is the use of base units, sometimes referred to as SI units. The principle behind using base units is that every single measurable quantity is measure one or more of 7 base units, which are:

Length - Measured in meters (m)
Mass - Measure in Kilograms (Kg)
Time - Measured in seconds (s)
Electric Current - Measured in Amperes (A)
Temperature - Measured in Degrees Kelvin (K)
Luminosity - Measured in Candela (cd)
Amount of substance - Measured in Moles (mol)

In physics, all measurements can be measured using a combination of these 7 base units. Lets use Force, for example. We know that Force is directly equal to mass multiplied by acceleration. Acceleration is a measurement of how velocity changes over time, so acceleration is equal to speed divided by time. Speed is a measurement of distance over time, so hence:

F=ma

m = Mass, measured in Kilograms (Kg)

a = Acceleration, measured in velocity/time which is velocity per second

velocity = Distance over time which is equal to meters per second or ms^-1

Hence, acceleration = ms^-1 multiplied by s^-1 which is equal to ms^-2

So therefore Force (F) is measured by Kilogram, meters per second squared, equally written as:

F ≡ Kg m s^-2   ('≡' - is the same as/equivalent to)

A force on an object is measured in newtons. One newton indicates one unit of force. As we can see, the base units for the measurement of newtons is 'Kg m s^-2'. This means that one newton is the forced required to increase the velocity of a body of mass 1 Kg by an accelerate of 1 ms^-2. Using simple equations such as this, we can find out what units are measured in and even derive new equations by comparing base units.

There is one other benefit to deriving base units in that it allows you to test whether an equation is homogenous. If we had an equation of Force equals Speed (F=v) then we would know this equation is not correct as the base units are different. For an equation to work it the base units must be homogenous. However, be wary; not all homogenous equations are correct. Take this equation for example.

F ≠ 2 ma   ('≠' - is not equal to)

We know that force is proportional to mass multiplied by acceleration and so, in respects to base units, this equation is homogenous. However, the additional constant '2' changes the equation's output by a factor of two and gives a force that is too large. Remember, an equation must be homogenous to be correct, but an equation is not necessarily correct if it is homogenous.

Using these basic principles and a bit of common sense, you can tackle most practical physics simply using suitable equations. Knowing when and how to apply certain equations is vital to understanding different problems and these simple tips will prepare you for even some of the most complex of physics. As with mathematics, theories can become very complex and hard to grasp but, at the end of the day, the process of mathematics boils down to addition, subtraction, multiplication and division among various numerical values.

For more information or quick reminders on mathematical terminology, meanings of symbols or values of constants, please refer to the glossary.

Please also note the capitalisation of certain variables. A capital 'F' denotes a force, whilst a lowercase 'f' denotes a frequency. As with 'a' showing acceleration, whilst 'A' shows an Amplitude - a measurement of current in an electrical circuit. Voltage is similarly measured in Volts (V) whilst velocity is recorded as a lowercase 'v', usually written in italic form as a lowercase and uppercase V are very similar.

2. Differences in Science and pseudosciences

This chapter points out the various problems and fallacies with pseudoscience, shows us the importance of the use of critical analysing against all scientific theories and further iterates the importance of peer reviewed papers. Pseudoscience promotes lazy thinking, improper methodology and bad reasoning and should be avoided at all costs; here we shall look at why. So, firstly, what is pseudoscience?

Pseudoscience is a form of study often loosely based on applied science, or claims to be an applied science, but is backed by little or no evidence. The term is usually used in a derogatory sense to demote obscure and non-verified scientific claims such as cosmology or alternative therapies such as homeopathy.

Pseudoscience can often masquerade as an applied science, usually by incorporating well-known scientific facts with subtly placed and unproven claims or using scientific jargon or terminology to make a hypothesis sound more plausible, such as using words like quantum, dynamic or sub-atomic. Pseudoscience can be the result of a lust for fame, genuine ignorance to a subject or even simply a promotion of superstitious thinking.

Pseudoscience is well defined by Wikipedia as being…

“…A methodology, belief, or practice that is claimed to be scientific, or that is made to appear to be scientific, but which does not adhere to an appropriate scientific methodology, lacks supporting evidence or plausibility, or otherwise lacks scientific status. The term comes from the Greek root pseudo- (false or pretending) and "science" (from Latin scientia, meaning "knowledge"). An early-recorded use was in 1843 by French physiologist François Magendie, who is considered a pioneer in experimental physiology.

Other classic features of pseudoscience are the failure or evasion to peer reviews. As mentioned in the first chapter, peer reviews are perhaps the most important aspect of the Scientific Method as it allows a hypothesis to be independently tested and verified. This process helps to refine theories based on poor reasoning and eliminate theories that are not properly tested or verified, such as most pseudoscientific claims. If a claim holds little water under careful inspection, peer reviews will often find the errors in the theory. Even accidental errors can be included in a publication and if a third party does not test the original hypothesis, the results cannot necessarily be trusted.

Pseudoscience can occasionally be hard to spot, but critical thinking can often highlight the problems with a pseudoscience claim. A good example of a particularly transparent pseudoscience claim, proposed as a money-spinner, is oxygenized water. This example was chosen as it predominantly incorporates accepted scientific claims, but applies various false or misleading assertions in order to reach an fabricated conclusion. The claim for oxygenated water is that if we pumped more oxygen into water, the water will help us perform better by allowing more oxygen into the body and brain. As we know, our body relies on oxygen to perform, and a lack of oxygen impairs our abilities. The market was aimed at primarily athletes as an alternative to sugary drinks, but I suspect it was predominantly aimed at idiots!

It first glance, it would seem plausible. It is a well-known fact that oxygen is a vital component in the functioning of our body, and more oxygen could logically boost performance, but we have to remember that too much oxygen is poisonous and, whilst there would certainly not be an unhealthy dose of oxygen in oxygenated water, is this excess oxygen actually beneficial?

Furthermore, oxygen is absorbed into the lungs, an organ very well evolved to cope with extracting large quantities or oxygen from it’s surroundings. The lungs are made with many crinkled, cauliflower shaped walls that dramatically increase the surface area and hence allow much more oxygen to be absorbed. The walls of the alveoli are also incredibly then to allow oxygen to be absorbed more efficiently into the body. This means then when we breathe in, out lungs fill with air and quickly absorb oxygen that can be transported around the body to where it is needed.

Liquids, on the other hand, flows not into the lungs but rather flow into the stomach, through the small intestine and into the large intestine where the water is extracted. Oxygenated water follows the same path and never reaches the lungs, so the excess oxygen in the water is never efficiently absorbed into the water and hence oxygenated water is no more beneficial than normal water.

This may seem a tame misunderstanding, but pseudoscience can have almost devastating consequences on both education and health. Perhaps one of the most commonly practiced for of pseudoscience in almost all cultures is alternative medicine or alternative therapies. Alternative therapies such as homeopathy have been known to replace conventional therapies such as chemotherapy in various cancer cases, and can have very real implications on the lives of others.

It can equally be pointed out that by very definition, alternative therapies do not, in practice, actually work. An alternative therapy is so named because the therapy is not supported by conventional medicine. This is because the therapy has either never been scientifically tested, or has been tested and failed the tests. These therapies usually offer no evidence as to how or why they work, or the evidence is fabricated.

If an alternative therapy is tested in a controlled environment and shows conclusive or tangible benefits, or the patient shows a defined improvement that can be attributed to the therapy in question, the therapy ceases to be an alternative therapy and becomes a mainstream or conventional therapy. Based on this, alternative therapies can never honestly be trusted over conventional therapies based on careful testing, accurately defined theories such as Germ Theory, and repeated tests and experiments.

However, pseudoscience often takes further strolls up the stream of absurdity, often into the realms of theology, philosophy and religion. Often people claim to use science to prove certain theological ideologies such as the existence of a God or gods.

The argument for the existence of God is certainly not scientific, and in the eyes of Science, God does not exist. That is not to say that there is no God, merely that there is not a scientific process to prove God's existence so therefore, in terms of Science, there is no God. Perhaps in another domain such as philosophy there could be a robust argument for his exist, though personally I remain dubious or the existence of a theistic or deistic entity.

Firstly, God cannot be directly or indirectly observed. Whilst in particle physics we may not be able to see many particles directly, we know that they exist from tracks left behind in bubble chambers. God, however, leaves no such tracks so there is absolutely no empirical evidence for the existence of God. God is also not falsifiable, i.e. there is not way to disprove or prove God’s existence. This does not adhere to the Scientific Method. To provide an explanation for how God could exist, a set of robust and empirical facts or hypotheses must be proposed and then tested. If there is no way to prove or disprove the hypothesis then the hypothesis cannot be appropriately tested. Therefore, we cannot test for God’s existence and therefore not scientifically prove or even assume God’s existence in any way.

But, as a skeptic to God, should an atheist or agnostic feel a need to disprove God? After all, the hypothesis is non-scientific and improvable, but even if this is not taken into consideration, it is the task of he who originally proposed the existence of a deity to prove this hypothesis by attempting to disprove the hypothesis.

If you were told that a pixie was hiding in your closet, you would most likely not choose to believe this. You would remain sceptical and ask for some form of evidence as to the pixies existence, or - in relation to other events - evidence to why this hypothesis is correct. It would not be up to you to disprove the pixie, as the hypothesis was not proposed by you. It would be up to he who originally postulated the existence of the pixie to prove to you the existence of the supernatural entity. This could be perhaps accomplished by opening the door. If there is a pixie, the hypothesis is correct, and if not, the hypothesis is most likely wrong. Now imagine that instead dwelling in the closet, the pixie was living in the sky. Does this analogy change in any way? It is still the endeavor again of he who originally postulated the existence to prove this hypothesis. We can no longer just open the door anymore, though, so the hypothesis must be tested in another way.

Examining the above analogy, you may have noted that, to adhere to the Scientific Method, you must attempt to disprove the hypothesis of the God’s existence that is impossible. As we cannot detect God in any way, we can’t disprove God in any way, so there is no way to test our hypothesis and therefore we cannot deduce a valid hypothesis, theory or law of God’s existence. Again, scientifically, God does not and cannot exist.

Among other problems with pseudoscience or religious claims such as God's existence, many attempt to prove God's existence based on the assumption that God exists and attempting to find evidence to prove this hypothesis. In practice, Scientists attempt to accumulate all available evidence and build their theories based on this evidence: no verified evidence is discarded. Science is able to change as technology and understanding progresses, but religion does not. It is stagnant in its view, and rarely accepts mistakes in the face of mounting evidence.

Nevertheless, I sincerely doubt, despite not being able to detect God either directly or indirectly OR being able to test the hypothesis that God exists OR supply an accurate hypothesis based on all the evidence that any theologians or members of the priesthood would attempt to disprove God in order to prove his existence. This undermines the concepts of faith.

1. A brief introduction into the processes of Science

Science is important; there is no denying it. It affects us all in immeasurable ways, and it is always amazing to see some people so readily discredit science through sheer ignorance and idiocy. Science is often misinterpreted, but people don’t like to admit it. As science becomes more and more complex, it becomes harder and harder to grasp. Science is so diverse now, that to even stay on top of one branch of science can be difficult. But to even understand any branch science, you must first understand what science is. So what is it?

If you were asked to define Science, what would you say? It may sound a silly question. After all, Science is Science. It is, to many, merely a combination of Biology, Physics and Chemistry, but Science is so much more than just three individual disciplines. Science is a complex subject, spanning many areas of knowledge, and Science is often completely misunderstood.

Science envelopes many different areas of study and there are many different fields of science, such as: Zoology and Biological Science; Mechanical and Quantum Physics; Chemistry, Virology and Medical Science; Mathematics and Mathematical Science; Social Sciences; and Engineering. Science is so broad that the best way to define the discipline is to define the process, a process called the Scientific Method.

The Scientific Method is a process of describing how an event takes place, typically making predictions about future events based on the data and evidence accumulated from the observations. By design, this method usually supplies the best possible explanation based on the available knowledge, but that is all.

Science does not, and has never claimed to explain why an event takes place; that is not sciences domain. That is the domain of philosophy. In science, the Theory of Abiogenesis, for example, doesn’t justify why life is here, just how life originated. The theory describes how life – i.e. an organism capable of growth and/or reproduction or replication – may have originated from natural, organic matter. Similarly, the Theory of Evolution also does not claim to know why humans are here, but simply describes how humans, and other animals, may have developed. Evolution describes nothing more than a process of change in allelic frequency over time due to natural selection and genetic drift.

Science never claims to know why anything has ever happened, or why anything ever will because the question “why?” is not necessarily observable. If we investigate a murder, we can see how the murder has taken place using empirical evidence. This could include a gun found at the scene with gunpowder around the nozzle and a matching bullet lodged in the victim’s skull, but we cannot necessarily assert why, because the evidence is not empirical. There could be many reasons why the murder took place: for money, for a woman or for personal convictions. This is why philosophy has so many views, and none are necessarily right or wrong, just perhaps more plausible.

This is not to say that philosophy and science are completely separate entities. Both philosophy and science cross intrinsically, and many philosophical principles are used to argue cases in science and vice-versa. Stolen money at the scene of murder may indicate a reason why the murder took place by using empirical evidence, but this is still not a descriptive claim of how the murder took place. The money may have been stolen as a cover-up to the deed, or by another person unrelated to the original incident.

Science was once considered a branch of philosophy: a Natural Philosophy. However, it is the outcome of these events – and the process of developing our understanding – that separates the two modern disciplines. Science may incorporate areas of philosophy (most notably logic) and philosophical concepts such as morals may affect science and the route taken in scientific discovery, but the conclusions are still scientific.

Indeed, in rare aspects, the line separating philosophy and science can become very blurred, but whilst a philosopher may use scientific concepts to back up a philosophical argument, but the argument is still philosophical.

The Scientific Method, in its simplest form, works by the derivations of laws and theories based on a hypothesis proposed from observations of an event. Usually, an event is witnessed and evidence of certain events is gathered, such as a lead ball falling to the ground when dropped. The evidence that the ball falls is visual, as well as mathematical, with a measurement of displacement from its original position and a mark on the ground from where the ball landed. A hypothesis is then derived from this, such as Newton’s theories of gravitational attraction.

Once a hypothesis is derived from the observations, the hypothesis needs to be critically analysed and tested. If a scientist who proposed the hypothesis wants to prove the hypothesis, be may use a biased test that he knows will prove the hypothesis correct. So, to remove bias, Scientists usually attempt to disprove the hypothesis. If the hypothesis can be proved wrong, the hypothesis is immediately discarded or modified. If the hypothesis cannot be proven wrong it is proposed as a theory.

If the hypothesis survives numerous tests, then the results are published. This is perhaps the most important part of the Scientific Method, because it allows other Scientists to review the tests and repeat the tests to make sure the results are not fabricated. If certain results are found to not fit in with the predictions made by the theory, then the theory must be modified to account for these results. If the theory is unable to account for these results, the theory is discarded, and a new hypothesis must be derived. This process is called the "peer review" and is a failsafe against scientists proposing untested or fabricated theories, often for personal gain.

This demonstrates the strength of a scientific theory, and highlights how the term “theory” is often misinterpreted as a hypothesis. A person who asserts that a scientific theory is “Just a theory, and therefore unproven” demonstrates their ignorance toward the Scientific Method. A theory, in Science, must – by default – be backed by shear amounts of evidence and has usually been tested countless times under huge inscrutability. In fact, the NAS (Nation Academy of Sciences) defines a theory as “A well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.”

This segment of an article from Scientific America demonstrates in more detail the differences in a hypothesis, theory and law.

"Many people learned in elementary school that a theory falls in the middle of a hierarchy of certainty--above a mere hypothesis but below a law. Scientists do not use the terms that way, however. According to the National Academy of Sciences (NAS), a scientific theory is "a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses." No amount of validation changes a theory into a law, which is a descriptive generalization about nature. So when scientists talk about the theory of evolution--or the atomic theory or the theory of relativity, for that matter--they are not expressing reservations about its truth.

"In addition to the theory of evolution, meaning the idea of descent with modification, one may also speak of the fact of evolution. The NAS defines a fact as "an observation that has been repeatedly confirmed and for all practical purposes is accepted as 'true.'" The fossil record and abundant other evidence testify that organisms have evolved through time. Although no one observed those transformations, the indirect evidence is clear, unambiguous and compelling.

"All sciences frequently rely on indirect evidence. Physicists cannot see subatomic particles directly, for instance, so they verify their existence by watching for telltale tracks that the particles leave in cloud chambers. The absence of direct observation does not make physicists' conclusions less certain."

Source - www.scientificamerican.com

We can see from here that empirical evidence is important to the Scientific Method. This can relate to the earlier analogy of the murder scene, where the police may accumulate factual evidence on the scene as to how the murder took place, but until they find the suspect of the murder and interrogate him, they may not know for sure why the murder took place.

Documentation, as earlier mentioned, is perhaps the most important aspect to science. It allows all research to be referenced throughout the world, and results to be repeatedly tested and verified under different conditions. It allows us to refer to basic principles and derive new laws or theories based on those principles.

Under no circumstances should any theory be taken on merits of authority or superficial plausibility. Many people may discredit theories by the likes of Sir Charles Darwin because they felt he was a bad role model. People claim, quite unrightfully, that Darwin upheld slavery and therefore his Theory of Evolution by Natural Selection could not be trusted as it was “evil”. Despite the fact that Darwin was fervently in support of the abolition of the slave trade and was almost cast off his infamous Beagle voyage after a dispute with the ships captain over similar matters, Darwin’s personal convictions do not play a part in the validity of his widely accepted theory. A scientific theory must always be taken on its own merits, and never on those who uphold or propose the theory.

Aristotle was, even in his lifetime, an infamous philosopher and scientist. So great was respect for Aristotle that almost all of his scientific claims remained unchallenged in his lifetime, from the insightful to the absurd. Among many other, more bizarre claims, Aristotle originally proposed – and it was accepted as a fact – that heavier objects would fall faster because they weighed more. It would seem logical: if you dropped a small lead ball, it will leave a small dent in the floor. If you dropped a huge lead boulder, it would leave a crater. Many people accepted this as a fact and it seemed so obvious that no one even bothered to test this assumption. It was not until the 17th century that Galileo demonstrated that this was not the case by dropping 2 balls of the same material, but different mass, off the side of the Leaning Tower of Pisa to demonstrate that their time of decent was the same. This meant that the acceleration on an object on the earth’s surface is the same.

This was later verified through Sir Isaac Newton’s theories of gravity, where Newton proposed that the force acting on an object is equal to the objects mass multiplied by the objects acceleration: F=ma (Force = Mass x Acceleration). This showed us that, whilst the 2 objects were moving at the same acceleration, the force exerted by the objects could be different depending on the objects mass, hence showing why the larger lead ball of greater mass left a much larger crater. It fell at the same speed but with more force, and therefore more energy.

If Galileo had not demonstrated and documented that all objects, regardless of size or mass, do not fall at the same speed, then Sir Isaac Newton would not have been able to build on Galileo’s work and further derive his own theories of gravitational attraction, and forces would not be understood. In fact, almost all aspects of modern day life would be completely different.

It is by building off the works of great thinkers of the past, and developing and deriving from their theories that science can progress, for Sir Isaac Newton famously quoted:

“If I have seen further than others, it is by standing upon the shoulders of giants.” - Sir Isaac Newton