Physics paper 2
A level graded questions and approved answers
What happens when an object falls and there's no air resistance? - ✔✔✔Energy lost from the
g.p.e store = energy gained in the kinetic energy store
What does air resistance do when acting against falling objects? - ✔✔✔It causes some energy
to be transferred to other energy stores e.g. the thermal energy stores of the object and the
surroundings
Elastic potential energy formula - ✔✔✔E=1/2ke²
E.P.E(J) = 0.5 x spring constant(N/m) x extension²(m)
What is SHC? - ✔✔✔The amount of energy needed to raise the temperature of 1kg of a
substance by 1°C
SHC formula - ✔✔✔E=mcθ
Change in thermal energy (J) = mass(kg) x SHC(J/kg/°C) x temperature change(°C)
What is the conservation of energy principle? - ✔✔✔Energy can be transferred usefully, or
stored or dissipated (wasted energy), but can never be created or destroyed
What is power? - ✔✔✔The rate of energy transfer, or the rate of doing work
What is 1W equal to? - ✔✔✔1J of energy transferred per second
,Power Equation 1 - ✔✔✔E=Pt
Energy transferred (J) = power(W) x time(s)
Power Equation 2 - ✔✔✔W=Pt
Work done(J) = power(W) x time(s)
What is conduction? - ✔✔✔The process where vibrating particles transfer energy to
neighboring particles
Energy is transferred to thermal stores of the object - this energy is shared across the kinetic
energy stores
What is thermal conductivity? - ✔✔✔A measure of how quickly energy is transferred through
a material via conduction
What is convection? - ✔✔✔Where energetic particles move away from hotter to cooler
regions
Energy is transferred to the thermal energy stores of the object and is shared across the kinetic
stores
What do radiators create? - ✔✔✔Convection currents
Convection currents - process - ✔✔✔1) Energy is transferred from the radiator to the nearby
air particles by conduction
2) The air by the radiator becomes warmer and less dense as the particles move quicker
3) The warm air rises and displaces the cooler air, which is then heated by the radiator
4) The previously heated air transfers energy to the surroundings - the air cools, becomes
denser and sinks
, What does lubrication do? - ✔✔✔Reduce frictional forces
Energy Stores - ✔✔✔
1) Elastic potential
2) Gravitational potential
3) Thermal
4) Electrostatic
5) Nuclear
6) Chemical
7) Kinetic
8) Magnetic
9) Light
10) Sound
How is energy transferred? - ✔✔✔1) mechanically - force doing work
2) Electrically - work done by moving charges
3) Heating/Radiation - light, sound
How can work be done? - ✔✔✔When a current flows or by a force moving an object
Kinetic energy formula - ✔✔✔E=1/2mv²
Kinetic energy (J) = 0.5 x mass(kg) x speed²(m/s)
Gravitational potential energy formula - ✔✔✔E=mgh
G.P.E (J) = mass(kg) x gravitational field strength (N/kg) x height (m)
What does insulation do? - ✔✔✔Reduce the rate of energy transfer by heating
A level graded questions and approved answers
What happens when an object falls and there's no air resistance? - ✔✔✔Energy lost from the
g.p.e store = energy gained in the kinetic energy store
What does air resistance do when acting against falling objects? - ✔✔✔It causes some energy
to be transferred to other energy stores e.g. the thermal energy stores of the object and the
surroundings
Elastic potential energy formula - ✔✔✔E=1/2ke²
E.P.E(J) = 0.5 x spring constant(N/m) x extension²(m)
What is SHC? - ✔✔✔The amount of energy needed to raise the temperature of 1kg of a
substance by 1°C
SHC formula - ✔✔✔E=mcθ
Change in thermal energy (J) = mass(kg) x SHC(J/kg/°C) x temperature change(°C)
What is the conservation of energy principle? - ✔✔✔Energy can be transferred usefully, or
stored or dissipated (wasted energy), but can never be created or destroyed
What is power? - ✔✔✔The rate of energy transfer, or the rate of doing work
What is 1W equal to? - ✔✔✔1J of energy transferred per second
,Power Equation 1 - ✔✔✔E=Pt
Energy transferred (J) = power(W) x time(s)
Power Equation 2 - ✔✔✔W=Pt
Work done(J) = power(W) x time(s)
What is conduction? - ✔✔✔The process where vibrating particles transfer energy to
neighboring particles
Energy is transferred to thermal stores of the object - this energy is shared across the kinetic
energy stores
What is thermal conductivity? - ✔✔✔A measure of how quickly energy is transferred through
a material via conduction
What is convection? - ✔✔✔Where energetic particles move away from hotter to cooler
regions
Energy is transferred to the thermal energy stores of the object and is shared across the kinetic
stores
What do radiators create? - ✔✔✔Convection currents
Convection currents - process - ✔✔✔1) Energy is transferred from the radiator to the nearby
air particles by conduction
2) The air by the radiator becomes warmer and less dense as the particles move quicker
3) The warm air rises and displaces the cooler air, which is then heated by the radiator
4) The previously heated air transfers energy to the surroundings - the air cools, becomes
denser and sinks
, What does lubrication do? - ✔✔✔Reduce frictional forces
Energy Stores - ✔✔✔
1) Elastic potential
2) Gravitational potential
3) Thermal
4) Electrostatic
5) Nuclear
6) Chemical
7) Kinetic
8) Magnetic
9) Light
10) Sound
How is energy transferred? - ✔✔✔1) mechanically - force doing work
2) Electrically - work done by moving charges
3) Heating/Radiation - light, sound
How can work be done? - ✔✔✔When a current flows or by a force moving an object
Kinetic energy formula - ✔✔✔E=1/2mv²
Kinetic energy (J) = 0.5 x mass(kg) x speed²(m/s)
Gravitational potential energy formula - ✔✔✔E=mgh
G.P.E (J) = mass(kg) x gravitational field strength (N/kg) x height (m)
What does insulation do? - ✔✔✔Reduce the rate of energy transfer by heating
