Energy Stores and Transfers

Question 1

is kinetic energy a store or a transfer of energy?

Answer 1

store

Question 2

is sound energy a store or a transfer of energy?

Answer 2

transfer

Question 3

is chemical energy a store or a transfer of energy?

Answer 3

store

Question 4

is gravitational potential energy a store or a transfer of energy?

Answer 4

store

Question 5

is internal (thermal) energy a store or a transfer of energy?

Answer 5

store

Question 6

is electric energy a store or a transfer of energy?

Answer 6

transfer

Question 7

is light energy a store or a transfer of energy?

Answer 7

transfer

Question 8

is electrostatic energy a store or a transfer of energy?

Answer 8

store

Question 9

is elastic potential energy a store or a transfer of energy?

Answer 9

store

Question 10

is magnetic energy a store or a transfer of energy?

Answer 10

store

Question 11

is heat (radiation) energy a store or a transfer of energy?

Answer 11

transfer

Question 12

is mechanical work (involving forces) energy a store or a transfer of energy?

Answer 12

transfer

Question 13

a wooden block is falling. which of the blocks energy stores is decreasing?

Answer 13

gravitational potential

Question 14

a wooden block is falling. which of the blocks energy stores is increasing?

Answer 14

kinetic

Question 15

where did the energy transfer to when the block landed?

Answer 15

the ground, surroundings

Question 16

In what form is energy stored in your phone?

Answer 16

chemical (battery)

Question 17

What energy store is decreasing while the candle or burner is burning?

Answer 17

Chemical

Question 18

Where is energy transferred to while the candle or burner is burning?

Answer 18

Internal energy of surroundings (thermal)

Question 19

What processes makes a candle or bunsen burner burning energy transfer happen?

Answer 19

Heat and light (waves)

Question 20

What energy store increases when you wind up the toy? (Hint: when you wind up the toy, you tighten up a spring inside it.)

Answer 20

Elastic potential energy

Question 21

what is the equation for Gravitational Potential Energy

Answer 21

GPE = mgh
g= constant 9.8m/s2

Question 22

Which 2 things affect an object’s KE?

Answer 22

The object’s SPEED

The object’s MASS

Question 23

what is the equation for kinetic energy

Answer 23

KE=1/2 mv^2
m=mass (kg)
v= velocity (m/s)

Question 24

when compressed or streched a spring gains ……………..

Answer 24

potential energy

Question 25

what is elastic potential energy?

Answer 25

the energy stored by the deformation of any elastic object (eg. The stretching of a rubber band).

Question 26

what is the equation for elastic potential energy

Answer 26

``` EPE = 1/2kx^2 x= extention k= constant (N/m) ```

Question 27

what is power?

Answer 27

Power is the rate of energy transfer, measured in Watts (W)

Question 28

what is the equation for power?

Answer 28

Power (W) = Energy transferred (J) / Time taken (s)

Question 29

Where does the energy eventually end up?

Answer 29

Energy eventually ends up as internal (thermal) energy of | the surroundings

Question 30

As energy is transferred to the surroundings it becomes less concentrated. What is the word we use in physics for less concentrated?

Answer 30

‘dissipated’

Question 31

The amount of energy wasted by a system indicates how | ................ the system is.

Answer 31

The amount of energy wasted by a system indicates how | efficient the system is.

Question 32

what are the equations for efficiency

Answer 32

Efficiency = useful energy transferred by the device (J) / total energy supplied to the device(J) Efficiency = useful power transferred by the device (W) / total power supplied to the device(W)

Question 33

No device is ......... efficient and the wasted energy is usually spread out (...........) to the ......... (thermal) of the .........

Answer 33

No device is 100% efficient and the wasted energy is usually spread out (dissipated) - internal (thermal) of the surroundings.

Question 34

what does the width of the top arrow represnt in a sankey diagram

Answer 34

the efficient energy

Question 35

what does the width of the bottom arrow represent in a sankey diagram

Answer 35

the energy wasted

Question 36

what do the top and bottom widths of the sankey diagrams add up to

Answer 36

the total energy input