physics paper 1

Created by

ansaaf salam

Cards (136)

System 
An object or group of objects
Energy transfer when a force acts on an object
1. Kinetic energy store → Gravitational potential energy store
2. Gravitational potential energy store → Kinetic energy store
3. Kinetic energy store → Thermal energy store
4. Chemical energy store → Kinetic energy store
5. Kinetic energy store → Thermal energy store
6. Thermal energy store → Kinetic energy store
Law of conservation of energy: energy cannot be created or destroyed
Kinetic energy 
Energy of a moving object, calculated using Ek = 0.5 x m x v^2
Elastic potential energy 
Energy stored in a stretched spring, calculated using Ee = 0.5 x k x e^2
Gravitational potential energy 
Energy gained by an object raised above ground level, calculated using Ep = m x g x h
Thermal energy change 
Energy stored or released as temperature changes, calculated using ΔE = m x c x Δθ
Specific heat capacity 
Amount of energy required to raise the temperature of 1 kg of a substance by 1°C
Power 
Rate of energy transfer, measured in watts (J/s)
Energy can be transferred usefully, stored or dissipated
Energy dissipation 
Occurs due to friction, air resistance, and sound energy
Higher thermal conductivity of walls
Higher rate of energy transfer by conduction, faster cooling
Thicker walls 
Lower rate of energy transfer by conduction, slower cooling
Energy efficiency 
Useful output energy transfer / Total input energy transfer
Ways to reduce unwanted energy transfers and improve efficiency 
Lubrication to reduce friction
Thermal insulation to reduce rate of energy transfer
Streamlined shaped objects to oppose air resistance
Tighten loose parts to reduce vibrations and sound energy
Renewable energy resource 
Resource that is being replenished as it is used
Non-renewable energy resources 
Fossil fuels
Nuclear fuel
Renewable energy resources 
Biofuel
Wind power
Hydroelectricity
Geothermal energy
Tidal power
Wave power
Solar energy
Uses of energy 
Transport
Electricity generation
Heating
Energy demands 
Higher in the evening
Higher in the winter
Reliability of energy resources
Non-renewable energy is more reliable due to availability
Renewable energy is used to cope with high demand
Wind, wave, tidal power rely on the wind
Hydroelectricity relies on precipitation
Solar power relies on sunlight
Geothermal energy
Tidal power 
High tides are forced through generators in a barrage
Wave power 
Waves are used to drive generators by a rocking motion
Solar power 
Converting solar energy into electricity using solar cells
System 
An object or group of objects
When a force acts on an object
Transfer of energy
As an object is projected upwards
Kinetic energy store → Gravitational potential energy store
As an object falls
Gravitational potential energy store → Kinetic energy store
As a moving object hits an obstacle, e.g. the ground
Kinetic energy store → Thermal energy store
As an object accelerates 
Chemical energy store → Kinetic energy store
As a vehicle decelerates
Kinetic energy store → Thermal energy store
As a liquid is heated to boil
Thermal energy store → Kinetic energy store
Law of conservation of energy: energy cannot be created or destroyed
Kinetic energy 
Energy of a moving object
Elastic potential energy 
Energy stored in a stretched spring
Gravitational potential energy 
Energy gained by an object raised above ground level
Thermal energy 
Energy stored or released as temperature changes
Specific heat capacity 
Amount of energy required to raise the temperature of one kilogram of a substance by one degree Celsius
Power 
Rate of energy transfer
Energy can be transferred usefully, stored or dissipated