calculate simple problems using work and energy.
- Calculate how much work is-clone when a small block of wood is dragged along a bench with a force of 2 N for 3 m.
- What is the force used to push a small flat deck truck a distance of 5 m when 4 kJ of energy is used up?
- The diagram shows a truck travelling at 50 km hr-1 (13.9 ms -1).
The mass of the truck is 2 tonne.
- A book weighing 0.3 kg is dropped off a table by accident and falls to the floor which is 0.7 m below the table top. What is the loss in gravitational potential energy?
Calculate the kinetic energy of the truck.
- If the truck’s kinetic energy is 400 kJ how fast is it going?
Holly walks up a flight of stairs 10 m high. Her mass is 35 kg.
6. Calculate her gravitational potential energy at the top of the stairs.
- If she accidentally drops a book of 500 g to the bottom of the stairwell what is the loss of gravitational potential energy of the book?
- How fast is the book travelling just before it hits the ground?