Momentum

A student carries out an investigation into a ball bouncing on a bench.

May/June 2015

A constant frictional force acts on a moving object for a brief period, so the object's momentum decreases. Which expression is used to calculate the time during which the force acts?

May/June 2023

Which equation includes two vector quantities?

May/June 2023

In a safety test, a car with mass 1100 kg is moving at 10 m/s when it hits a van of mass 3000 kg that is stationary. After the collision, the car and the van continue together with velocity v. Fig. 2.1 illustrates the car and van before and after the collision. The total momentum of the car and van is conserved during the collision.

May/June 2023

Fig. 1.1 presents the speed-time graph of a car moving along a straight horizontal road.

May/June 2023

A car with mass $750\,\text{kg}$ moves $400\,\text{m}$ at $25\,\text{m s}^{-1}$. It then speeds up to $35\,\text{m s}^{-1}$ and goes a further $400\,\text{m}$. What is the change in the momentum of the car due to acceleration?

May/June 2024

What is one possible unit of momentum?

May/June 2025

During a safety test, a car impacts a concrete block. The impulse applied by the block to the car is $14\,000\,\text{N s}$. The impact with the block takes $70\,\text{ms}$. Calculate the force on the car.

May/June 2025

Which expression represents impulse?

Oct/Nov 2023

A spacecraft with mass $300\,\text{kg}$ is travelling in a straight line through space at $8000\,\text{m s}^{-1}$.

Oct/Nov 2023

Trolley X, with mass $2.0\,\text{kg}$, is travelling rightwards at $2.0\,\text{m s}^{-1}$. Trolley Y, with mass $1.0\,\text{kg}$, is travelling leftwards at $1.0\,\text{m s}^{-1}$. The trolleys collide and then remain stuck together. The collision lasts for a total of $0.20\,\text{s}$. What is the average force acting on trolley X during the collision?

Oct/Nov 2024

A jet ski is a small boat built for carrying one or two people and moving at high speed on water. Fig. 1.1 shows a student riding on a jet ski. Inside the jet ski, a pump forces a high-speed jet of water backwards out of the rear. Fig. 1.1 includes labels for the arrow showing the direction of movement, the jet ski, and the jet of water.

Oct/Nov 2024

A rocket has mass $M$ when it is empty. It also carries an extra mass $M$ of fuel. The rocket and the fuel are moving at speed $v$. When the rocket engine is ignited, all of the fuel is ejected and the rocket’s speed rises to $2v$. What happens to the kinetic energy of the rocket?

Oct/Nov 2025

A car is stationary on a straight horizontal road. At time t = 0, the car starts to accelerate. Figure 1.1 illustrates how the car’s momentum changes with time.

Oct/Nov 2025

Fig. 3.1 depicts a firefighter aiming a jet of water at a wall. Diagram labels: firefighter, jet of water, wall, water. In 1.0 s, a horizontal volume of $7.5 \times 10^{-3}\,\text{m}^3$ of water reaches the wall at a speed of 24 m/s. The density of water is 1000 kg/m$^3$.

Oct/Nov 2025