Forces and Momentum · Paper 1 — Free Physics SL Practice Questions

A car of mass $1200 \text{ kg}$ is travelling at $20 \text{ m s}^{-1}$ along a straight horizontal road. The driver applies the brakes, exerting a constant braking force of $4800 \text{ N}$ on the car. What is the magnitude of the deceleration of the car?

A block of mass $2.0 \text{ kg}$ is pulled along a rough horizontal surface by a single horizontal force of $10 \text{ N}$. The coefficient of kinetic friction between the block and the surface is $0.15$. What is the magnitude of the acceleration of the block? (Take $g = 10 \text{ m s}^{-2}$.)

A tennis ball of mass $0.050\ \text{kg}$ travels horizontally at $30\ \text{m s}^{-1}$ toward a wall. It rebounds horizontally at $20\ \text{m s}^{-1}$ in the opposite direction after a contact time of $0.010\ \text{s}$. What is the magnitude of the average force exerted by the wall on the ball?

A car of mass $1200 \text{ kg}$ travelling at $15 \text{ m s}^{-1}$ east collides head-on with a truck of mass $1600 \text{ kg}$ travelling at $10 \text{ m s}^{-1}$ west. The vehicles lock together on impact. What is the velocity of the combined wreckage immediately after the collision?