- A ball of mass 4.5 kg is released from rest at the top of
a slope as shown. When it reaches the bottom of the sloe it is travelling at 2.5 ms-1.
- Calculate the potential energy of the ball at X.
- Calculate the kinetic energy of the ball at Y.
- Calculate the work done against friction while moving from X to Y.
- If the distance XY is 8.5 m, calculate the average force due to friction.
2 ms–I 3
- Two balls collide head-on as shoNvn.
The larger 4 kg ball rebounds at 1 ms-1. 4 kg
- Calculate the velocity of the smaller ball after impact.
- Show by calculation whether the collision is elastic or inelastic.
- A girl on a bicycle is cycling at a constant speed. The combined kinetic energy of the girl and her bicycle is 1 600 J. She then slows down.
What is the new combined kinetic energy of the girl and her bicycle when their combined momentum is half its previous value?
- A rocket of mass 1 500 kg slows down from 580 ms-1 to 120 ms-1 due to friction with the How much kinetic energy does it lose?
- The driver of a car travelling along a level road brakes sharply. The front wheels of the car lock producing a skid of 32.3 m long as the car comes to rest. The mass of the car including the driver is 1 050 kg. It is estimated that the frictional force while skidding
is 5 210N.
Calculate the velocity of the car just before its wheels locked.
- A trolley of mass 2 kg moving at 2 ms-1 collides in elastically– with an identical stationary trolley. After the collision., they move off coupled together.
How much kinetic energy is lost during the impact?
