Work Power and Efficiency

Question 1

which of these situations can increase the reaction time of a driver

Answer 1

D - driving for a long time without a break

Question 2

Describe how the energy of a ball changes as it drops towards the sand

Answer 2

• gravitational energy reduces
• kinetic energy increases
• total energy remains constant

Question 3

Explain how work is done when the balls impact the sand

Answer 3

• work is done displacing the sand

- as kinetic energy of the ball has been transferred

Question 4

Complete the sentence

the vector quantity is

Answer 4

FORCE

Question 5

wind (blank) energy

generator (blank) energy

Answer 5

kinetic

• electrical

Question 6

explain why the temperature of the lamp remains constant

Answer 6

• energy supplied and radiated

- at an equal rate

Question 7

() energy

() energy in the batteries

Answer 7

light energy

• chemical

Question 8

Explain why the temperature of the water increases and then stays constant

Answer 8

• water absorbs thermal energy
• then the water emits thermal energy
• more heat radiated at higher temperature
• input and output are balanced

Question 9

This statement is one example of the idea of

Answer 9

B - energy

Question 10

which of these describes power

Answer 10

C -

energy transferred per second

Question 11

Define work done

Answer 11

When an external force transfers energy to a system

Question 12

Which of these quantities change in bot size and direction while he is swinging?

Answer 12

B - his momentum