10 minutes maximum! Can you do it in 5?

1. Which of these statements is the best definition of power?

  • A. The total work done.
  • B. The total work done x the time taken.
  • C. The total work done x the distance travelled.
  • D. The rate at which work is done.

2. Which of these statements is the best definition of work done?

  • A. The energy used up by a system.
  • B. The energy wasted in a system.
  • C. The energy transferred in a system.
  • D. The energy stored in a system.

3. Which of the following correctly gives the units used for measuring work done and power?

 work done power
A
 watts joules
B
 watts volts
C
 joules volts
D
 joules watts

4. A builder carries a varying mass of bricks to the top floor of a building. Which of the following required the most power?

  • A. 10kg load lifted up in 60 seconds
  • B. 10kg load lifted up in 120 seconds
  • C. 20kg load lifted up in 60 seconds
  • D. 20kg load lifted up in 120 seconds
5. A wind turbine has a peak output of 0.15 MW. wind turbine

This is the same as:

  

 

6-8. Kettles are used to heat water using electrical power. The table below gives some data about 3 kettles. What are the missing values in the table?

  
Type of kettle Work Done Time taken Power
6. kettle A 40 000 J 80 s
7.
 kettle B 300 000 J 1 min
8. kettle C 40 s 2 kW
9+10. A solar panel is used to charge a phone on a camping trip.
The peak power output of the solar panel is 2 W. The phone needs 20 kJ to be fully charged. 		 

9. How long will it take to charge the phone?

  • A. 40 000 s
  • B. 10 000 s
  • C. 4 000 s
  • D. 1000 s

10. Julie needs her phone charging in just 1 hour. She wants to buy a more powerful solar panel. What power output from the solar panel is needed?

  • A. 5.6 W
  • B. 3.3 W
  • C. 20 kW
  • D. 0.18 W