ENEGY yr 9

Question 1

give the equation to weight and it’s units

Answer 1

w = mg
N = Kg x N/kg

Question 2

give the equation to gravitational potential energy and its units

Answer 2

Ep = mgh
J = Kg x N/Kg x m

Question 3

give the equation to elastic energy and give the units

Answer 3

Ee = 1/2ke^2
J = 1/2 x N/m x m

Question 4

give the equation to kinetic energy and give the units

Answer 4

Ek = 1/2mv^2
J = 1/2 x kg x m/s

Question 5

what is the order of a coal power station

Answer 5

furnace, boiler, turbine, generator

Question 6

give the equation to efficiency and it’s units

Answer 6

useful output energy
efficiency = ——————————
total input energy
J
efficiency = —
J

Question 7

give the ways energy is transferred

Answer 7

light and waves, electrical current, thermally, by a force

Question 8

what gas is also released in the burning of coal?

Answer 8

SO2

Question 9

give all the of the energy stores

Answer 9

kinetic, elastic, chemical, gravitational, thermal, nuclear, electric magnetic

Question 10

what is the main source of energy used by the uk?

Answer 10

biomass or wood chips

Question 11

give the equation to work done and it’s units

Answer 11

W = F x S
J = N x M

Question 12

what is biofuel

Answer 12

fuels that are made by harvesting plants such as trees

Question 13

give the equation to power and it’s units

Answer 13

E
P = —
t
J
w = —
s