Important Equations For Assessment 2 Part A

Question 1

What are the two ways of finding change in momentum?

Answer 1

Change in momentum = force x time
Change in momentum = mv - mu 
u is the initial velocity
v is the final velocity
m is the mass

Question 2

What does conservation of momentum state?

Answer 2

Momentum cannot be created or destroyed, so if two objects collide - sum of momentum before collision = sum of momentum after collision

(Mass 1 x initial velocity 1) + (mass 2 x initial velocity 2) = (mass 1 x final velocity 1) + (mass 2 x final velocity 2)

Question 3

What is the relationship between force and rate of change of momentum?

Answer 3

Force = rate of change of momentum

Question 4

How can you show that force is equal to the rate of change of momentum?

Answer 4

Acceleration = change in velocity / time taken
Force = mass x acceleration

Therefore force = mass x change in velocity / time taken
Momentum = mass x velocity, so we can say that:
Force = change in momentum / time taken
This is the same as force = rate of change of momentum