Momentum

A tennis ball of mass m moving horizontally with speed u strikes a vertical tennis racket. The ball bounces back with a horizontal speed v. The magnitude of the change in momentum of the ball is

• m(u + v)

• m(u - v)

• m(v - u)

• zero

A constant force of magnitude F is applied to a mass m for a time interval ∆t. The magnitude of the impulse given to the mass equals

• F / m

• F / ∆t

• F∆t

• F∆t / m

Two carts of mass m and M are connected by a compressed spring. After the carts are released, the cart of mass m moves with velocity v. The change in the momentum of mass M is

• mv

• -mv

• Mv

• -Mv

Two spheres of masses m₁ and m₂ are moving towards each other with speeds v₁ and v₂. The total change in linear momentum of the spheres as a result of the collision is:

• 0

• m₁v₁ + m₂v₂

• m₁v₁ − m₂v₂

• m₂v₂ − m₁v₁

A trolley M collides head-on with a trolley L. The mass of trolley M is greater than the mass of trolley L. The trolleys join together after the collision. Which statement is correct?

• The momentum of each trolley is conserved.

• Trolley M experiences a greater force than trolley L during the collision.

• The total force acting on the two-trolley system during the collision is zero.

• Kinetic energy is conserved.

Which is the correct unit of momentum?

• kg m s⁻¹

• kg m s⁻²

• kg m^-1 s⁻²

• kg m^-2 s⁻²

Which of the following graphs would have the same shape as a force - time graph?

• acceleration - time

• kinetic energy - time

• momentum - time

• velocity - time