Momentum & Impulse (Edexcel International A Level Physics)

A particle of mass m has kinetic energy E_k and momentum p. A second particle of mass 2m has kinetic energy 2E_k. Both particles are non‐relativistic.

Which of the following is equal to the momentum of the second particle?

The diagram shows the momentum of two trolleys, X and Y, before a collision. The mass of each trolley is 0.25 kg.

The two trolleys join together after the collision and move on with a velocity of 1 m s⁻¹ .

Which row of the table is correct for this collision?

	Momentum	Elastic or inelastic collision
A	conserved	elastic
B	conserved	inelastic
C	not conserved	elastic
D	not conserved	inelastic

A sphere travelling at speed v collides elastically with an identical sphere which is at rest.

After the collision, both spheres move off at an angle θ to the direction of travel of the first sphere, as shown. The spheres have the same speed as each other.

What is the speed of the spheres after the collision?