Energy and Forces I

Question 1

units for energy

Answer 1

• Joules

- Kilo Joules

Question 2

abbreviations for energy units

Answer 2

• J

- KJ

Question 3

how many J in a KJ

Answer 3

1000

Question 4

how many KJ in a J

Answer 4

0.001

Question 5

thermal energy store (2)

Answer 5

• energy store for how hot/ cold an object is

- some energy always there because it is physically impossible for an object to be less than -273 degrees Celsius

Question 6

what is the lowest possible temperature on earth

Answer 6

-273 degrees Celsius

Question 7

kinetic energy store

Answer 7

there will be energy in an object’s kinetic energy store if the object is moving

Question 8

chemical energy store

Answer 8

high in fuels, food and muscle tissue

Question 9

gravitational potential energy store

Answer 9

the higher an object is from the ground, the higher the gravitational potential

Question 10

how much gravitational potential energy is in an object that is on the ground

Answer 10

0

Question 11

how much kinetic energy is in a stationary object

Answer 11

0

Question 12

Law of conservation of energy

Answer 12

energy cannot be created or destroyed

energy can be stored or transferred

Question 13

if someone eats food and then runs where does the energy initially come from

Answer 13

chemical energy of the food

Question 14

if someone eats food and then runs where does the energy get transferred to next

Answer 14

chemical energy store of muscles

Question 15

if someone eats food and then runs where does the energy end up last

Answer 15

kinetic energy store of muscles AND thermal energy store of surroundings

Question 16

if someone burns wood where does the energy initially come from

Answer 16

chemical energy store of the wood

Question 17

if someone burns wood where does the energy get transferred to

Answer 17

kinetic and thermal energy store of the fire

Question 18

if someone burns wood where does the energy end up last

Answer 18

thermal energy store of surroundings

Question 19

what are 2 energy transfer mechanisms

Answer 19

weight/ gravity and waves

Question 20

what is gravity

Answer 20

the force that brings all objects with mass closer together

Question 21

what is the gravitational field strength on earth

Answer 21

9.8 N/kg

Question 22

weight

Answer 22

a force measured in Newtons that is affected by the mass and location of an object

Question 23

mass

Answer 23

measured in grams or kg and does not change, whatever the gravitational field strength might be

Question 24

formula for weight

Answer 24

weight (Newtons) = mass (kg) x gravitational field (N/kg)

Question 25

what is work done

Answer 25

the amount of energy transferred from one energy store to another

Question 26

formula for work done

Answer 26

work done (Joules) = force (N) x distance (metres)

Question 27

formula for distance

Answer 27

distance (metres) = velocity (m/s) x time (seconds)

Question 28

what is pitch

Answer 28

how high or low the sound is due to the speed of vibrations in a wave

Question 29

what is volume

Answer 29

how loud or quiet the sound is due to the strength of the vibrations in a wave