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Explain why atmospheric pressure decreases with increasing altitude. (3 marks)

Firstly, pressure is created by air molecules colliding with a surface. At an increased altitude there are fewer air molecules, and therefore a larger average distance between them. This means at this higher...
EB
Answered by Emily B. • Physics tutor
21170 Views

Help! How do I rearrange equations?

Being able to manipulate equations is a very useful skill in Physics. Consider, for example, the relationship between mass, density and volume. m = ρ x v In the above equation, the mass, m is the subject bec...
IP
Answered by Ijeoma P. • Physics tutor
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How do you calculate the total resistance of two resistors, R1 and R2, when they are in series and when they are in parallel?

When resistors are in series you may add up their resistances to find the total resistance, R Total = R1 + R2. However, when resistors are in parallel, it gets a little more complicated. You must use the equ...
JM
Answered by Jamie M. • Physics tutor
14929 Views

How many times further away from the pivot point of a seesaw does someone of double the weight have to sit in order for the it to balance?

Sum of moments in equilibrium must equal 0. The sum of clockwise moments must equal the sum of anticlockwise moments. W1 is the force exerted on the seesaw by the heavy person at distance D1 from the pivot a...
RM
Answered by River M. • Physics tutor
3369 Views

What is are elastic and inelastic collisions?

A collision is elastic when the total amount of kinetic energy in the system is conserved, there is no loss in kinetic energy. A collision is inelastic when the total amount of kinetic energy in the system i...
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Answered by Adam R. • Physics tutor
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