OCR GCSE 2018 - Energy

Page 1

 

1. Work done is measured in

  • A) joules
  • B) watts
  • C) coulombs
  • D) newtons
 

2. Which of these is NOT a store of energy?

  • A) chemical
  • B) gravitational potential
  • C) friction
  • D) kinetic

3-9. Choose the correct energy store in the following systems:

A bow and arrow transfers
energy into useful
energy.
A petrol engine transfers
energy into useful
energy.
Most of the energy wasted is lost as
energy.
 
A ball thrown upwards transfers
energy into useful
energy.

 

 

A motor on a train converts 60 000J of electrical energy into 45 000J of kinetic energy as the train accelerates.

train

10. What is 60 000J in kJ?
11. How efficient is the motor?
12. If it converts this energy in 15 seconds, what is the useful power output?

13. What is the formula for work done?

  • A) Work done = force x distance
  • B) Work done = force ÷ distance
  • C) Work done = mass x acceleration
  • D) Work done = mass ÷ acceleration

14. A tractor pulls a plough 2km across a field using a force of 8kN. What is the work done?

15-16. What are the missing labels on this energy flow diagram for a radio?

Electrical Energy

5000J

800J

 

 

Thermal energy