P1.2 - Energy and Efficiency

Question 1

What 3 things CAN be done with energy?

Answer 1

It can be transferred, stored or dissipated

Question 2

What 2 things CAN’T be done with energy?

Answer 2

It can’t be created or destroyed

Question 3

When energy is transferred, not all of it is transferred usefully, what happens to the rest?

Answer 3

It is wasted

Question 4

What can be used to show useful and wasted energy?

Answer 4

A Sankey diagram

Question 5

What effect does wasted energy have on the surroundings?

Answer 5

It is transferred, so the surrounding air heats up

Question 6

How can the efficiency of a device be calculated?

Answer 6

efficiency = useful energy out/total energy in (x100)

Question 7

What is pay back time?

Answer 7

How long it takes for an energy saving appliance to save the amount of money that it cost for a person

Question 8

How can waste energy be useful?

Answer 8

In heat exchangers

Question 9

What does a Sankey diagram show?

Answer 9

The efficiency of an appliance