A change in momentum happens when a force is applied to an object that is moving or is able to move. The total momentum in an explosion or collision stays the same.

What is momentum?

A moving object has momentum. This is the tendency of the object to keep moving in the same direction. It is difficult to change the direction of movement of an object with a lot of momentum.

Calculating momentum

You can calculate momentum using this equation:

p = m × v

• p is the momentum in kilograms metres per second, kg m/s
• m is the mass in kilograms, kg
• v is the velocity in m/s

• For example, what is the momentum of a 5 kg object moving with a velocity of 2 m/s?
• Momentum = 5 × 2 = 10 kg m/s

Direction

Notice that momentum does not just depend on the object’s mass and speed. Velocity is speed in a particular direction…