Momentum Introduction

MOMENTUM is defined as the MASS of an object multiplied by its VELOCITY.
The symbol for MOMENTUM is p.

formula: p = mv

So the units are kg.m.s-1

Momentum is a vector quantity, which means it needs a magnitude AND a direction in the answer. Momentum is also referred to as "quantity of motion".

Here are a few examples to get going!

Question 1
A trolley has a mass of 4kg, and a velocity of 2m.s-1 rightwards.

1.1 Write done the formula to calculate its momentum.
p = mv
1.2 Calculate the momentum.
p = mv
p= (4)(2)
p = 8kg.m.s-1 rightwards

Question 2
A trolley has a mass of 8kg, and a momentum of 24kg.m.s-1 rightwards.

2.1 What is the symbol for momentum?
p
2.2 Define velocity.
rate of change of displacement
2.3 Calculate the velocity
p = mv
24 = 8v
v = 3 m.s-1 rightwards
So it is easy to calculate the momentum of an object. But what do we learn from this?
As an example, a 2kg trolley moving at 10m.s-1 will have the same momentum as a 5kg trolley that is moving slower at 4m.s-1.
Both have a momentum of 20kg.m.s-1.
This is an important thing to know! For now, just be able to apply the p = mv formula, and calculate stuff!

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