physics paper 1

Question 1

what does conservation of energy mean

Answer 1

ENERGY cannot be created or destroyed

Question 2

what is energy measured in?

Answer 2

Joules (j)

Question 3

in an equation what does M mean

Answer 3

Mass

Question 4

what is a closed system?

Answer 4

a system where no energy is gained or lost from the surroundings

Question 5

what is kinetic energy equal to

Answer 5

0.5 X mass X speed^2

Question 6

what is gravitational potential energy equal to

Answer 6

mass X gravitational field strength X height

Question 7

elastic potential energy equation

Answer 7

0.5 X spring constant X extension^2

Question 8

the equation for thermal energy

Answer 8

mass X specific heat capacity X change in temp

Question 9

whats the equation for power

Answer 9

energy transferred / time

Question 10

whats the unit for power

Answer 10

watts (w) ( joules per second)

Question 10

whats the equation for efficiency

Answer 10

useful energy out / total energy in

Question 10

whats the equation for efficiency as a percentage

Answer 10

useful energy out / total energy in X100

Question 11

whats an example of a finite source

Answer 11

Fossil Fuels - coal, oil/

Question 12

whats an example of renewable sources

Answer 12

wind power - from wind turbines

Question 13

what is electricity

Answer 13

the flow of charge

Question 14

what is current

Answer 14

the rate of flow of charge

Question 15

what is charge measured in?

Answer 15

coulombs

Question 16

what is potential difference

Answer 16

how much energy is transferred per coulomb

Question 17

what is the equation for potential difference

Answer 17

energy transferred / charge

Question 18

what is the equation for current

Answer 18

charge/time

Question 19

what is resistance measured on

Answer 19

ohms

Question 20

are potential difference and current directly proportional?

Answer 20

yes