# Physics

What is physics

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myval37
30 July 2016
Physics is a type of science that studies matter and motion as well as how it interacts with energy and forces. There are many different branches of physics ranging from electricity, astronomy and forces. This is just a basic definition, I'm assuming you are asking this to help choose a subject? When looking at physics for taking a subject then you ave to think about if you enjoy looking at how things work.
Lauren D.
07 August 2016
I just had a look at Danie's answers. #18 and #20 are helpful, but #19 is very unhelpful.This question is nothing to do with air resistance - the aircraft is airtight - no air even enters or escapes! Centrifugal force is not a real force (centripetal force is the force you should talk about instead) and also nothing to do with this question. I can see why Danie said that free fall normally only happens in a vacuum because technically there are other forces that act such as drag (e.g. air resistance) - and even upthrust when moving through a fluid, but let's not go there. Even when falling through the air (which is not happening to the passengers in this question), however, these forces are normally ignored in secondary school physics questions. Any object falling where the only force acting on it is the force due to gravity is in free fall.So let me explain:For the passengers to experience weightlessness, they do need to be in free fall which means the only force acting on each person is their own weight. Normally if an aircraft flies horizontally, the seat in the aircraft pushes up on the passenger (called a reaction force which is equal in size and opposite in direction to the weight force pushing into the seat) - without the seat pushing up, the passenger would be in free fall and would fall through the bottom of the aircraft. But in this situation the aircraft is not flying horizontally. So without giving away the answer, why does the motion of the aircraft result in only the weight force and not the reaction force acting on each passenger? Remember there needs to be contact between the passenger and the seat for the reaction force to exist.Hope this is helpful, clears things up and is clear!
Sam P.
11 August 2016
At GCSE level most exam board specifications cover energy,forces,motion,and environmental impacts. Some boards include Earth in Space/Astronomy.
science_tutor
09 September 2016
Physics  is the stream of science  in which we deal with the study of nature  and natural  phenomenon and its mathematical  interpretation.Physics has its existence  in ontology ,the brance of philosophy  which deals with the study of existence.In physics  basically  a student discuss whether  the phenomenon  we are dealing  with is because  of its own attribute or because  of some external  effects.e.g. water  flows. This natural  phenomenon  is whether  due theattribute of water that it wants to flow or because  of some external  effect.A superficial discussion   will look like its the property  of water to flow. But the fact is different  water flows because of gravity.Besides  it has a tendency  to squeeze  inside in space water will not flow but for a sphere.Moreover  Physics  not only discuss  the law of nature  but alsoexpress it in the most reliable  language  i.e. mathematics.
anshu_awasthi
23 October 2017
Physics is a wide field of study which deals with the study of matter and natural forces. Also its the study of matter in its relation to energy.
maclus
07 May 2018