3.1-3.12 Efficiency and Energy

Question 1

What is meant by conservation of energy?

Answer 1

The total energy of an isolated system remains constant

Question 2

What energy changes occur when an object travels is projected upwards?

Answer 2

Kinetic Energy transferred to GPE and vice versa as it comes back down

Question 3

What are the 8 energy stores?

Answer 3

.Magnetic
.Thermal
.Chemical
.Kinetic
.Electrostatic
.Elastic potential
.Gravitational potential
.Nuclear

Question 4

What energy changes occur when an object travels up a slope?

Answer 4

.KE transferred to GPE and heat if friction is present

Question 5

What energy changes occur if a moving object hits an obstacle?

Answer 5

.KE transferred to sound

.KE transferred to obstacle if that moves to

Question 6

What energy changes would occur if an object is accelerated at a constant force?

Answer 6

.Object is having work done to it with gaining KE

.Whatever supplies the force is having its Energy transferred to KE

Question 7

What energy changes occur to a vehicle slowing down?

Answer 7

KE transferred to heat (through breaks)

Question 8

What energy changes occur through boiling water in a kettle?

Answer 8

.Electrical energy to thermal

Question 9

What happens to the net change if energy transfer occurs in a closed environment?

Answer 9

.No net change

Question 10

Give two ways efficiency can be increased through waste output

Answer 10

.Lubrication

.Thermal insulation

Question 11

If the thickness of the walls in a business are increased what happens to the heat loss?

Answer 11

.Greater thermal insulation so heat loss decreases

Question 12

How do air cavities cause heat loss?

Answer 12

.Heat loss by convection, fills in the gap and prevents air flow

Question 13

How can efficiency be increased?

Answer 13

.Reducing waste output

.Recycling waste output