Paper 1 - 1 Energy Flashcards
What is a system?
An object or group of objects
Describe the energy changes when a ball is thrown upwards
Kinetic energy into GPE and thermal
Describe the energy changes when an object hits an obstacle
Kinetic into Thermal and sound
Describe the energy changes in a torch
Chemical into electrical into thermal and light
State the equation and all units for kinetic energy
kinetic energy (J) = 0.5 x mass (kg) x speed squared (m/s)
State the equation and all units for GPE
g.p.e. (J) = mass (kg) x gravitational field strength (N/kg) x height (m)
Define specific heat capacity
the amount of energy required to raise the temperature of one kilogram of the substance by one degree celsius.
State the units for specific heat capacity
J/kg C
Define Power
Rate at which energy is transferred into a new form
State the equation with all units for Power.
Power (W) = energy (J) / time (s)
Define 1 W
An energy transfer of 1 joule per second
State the conservation of energy
Energy can be transferred usefully, stored or dissipated, but cannot be created or destroyed.
Define thermal conductivity
How well a material conducts energy. The higher the thermal conductivity of a material the higher the rate of energy transfer by conduction across the material.
How can heat loss from a building be minimised?
Using thicker walls and materials with a lower thermal conductivity
Define efficiency
How effective a device is at converting its input energy into a useful output form of energy
State the equation for efficiency
efficiency = useful output energy / total input energy
Efficiency is always between?
0 and 1 (decimal) or 0 % and 100% (percentage)
State the 3 fossil fuels
Coal, oil and gas
State the order of start up times from shortest to fastest of the three fossil fuels
Gas, Oil, Coal (fastest to slowest)
State two fuels used in a nuclear reactor
Uraninium (1) Plutonium (1)
Define a renewable energy resource
One that can be replenished and won’t run out
State the advantages of fossil fuels
Reliable (1) Short start up time of a few hours (1) cheap (1) can be used in many locations (1) doesn’t produce radioactive waste (1)
State the disadvantages of fossil fuels
Non renewable (1) Will run out (1) Produces carbon dioxide (1) which leads to global warming (1) Causes acid rain(1)
State the advantages of nuclear power
Reliable (1) A very concentrated source of energy (1) No carbon dioxide release (1) Doesn’t cause acid rain (1)
State the disadvantages of nuclear power
Slow start up time of a few days (1) Causes Radioactive waste (1) High decommissioning costs (1) Non renewable (1)
State the advantages of solar power.
Renewable (1) no fuel cost (1) no cardon dioxide (1) Doesn’t cause acid rain (1) can be used in remote locations (1)
State the disadvantages of solar power
Unreliable (1) Expensive to buy (1) Doesn?t produce much energy so need lots of solar cells (1)
State the advantages of wind
Renewable (1) Wont run out (1) no fuel cost (1) no cardon dioxide (1) Doesn’t cause acid rain (1)
State the disadvantages of wind
Unreliable (1) Visual pollution (1) Noise pollution (1) Don’t get much energy so needs a large area of wind turbines (1)
State the advantages of hydroelectric
Short start up time (1) Renewable (1) no fuel cost (1) no cardon dioxide emitted (1) Doesn’t cause acid rain (1)
Disadvantages of hydroelectric
Expensive to buy the dam (1) Flooding of surrounding areas (1) Damage to animal habitats (1)
Advantages of geothermal
Short start up time (1) Renewable (1) Wont run out (1) Low fuel cost (1) no cardon dioxide (1) Doesn’t cause acid rain (1)
Disadvantages of geothermal
Expensive to drill (1) Only suitable in certain locations (1)
Advantages of wave power
Renewable(1) Wont run out (1) Low fuel cost (1) no cardon dioxide (1) Doesn’t cause acid rain (1)
Disadvantages of wave power
Unreliable (1) Difficult to maintain and repair (1) Restricts shipping lanes (1)
Advantages of tidal
Reliable - as tides can be predicted (1) Renewable (1) Low fuel cost (1) no cardon dioxide (1) Doesn’t cause acid rain (1)
Disadvantages of tidal
Difficult to maintain and repair (1) Restricts shipping lanes (1)
Advantages of biomass
Reliable (1) Renewable (1) Carbon neutral (1)
Disadvantages of biomass
Release carbon dioxide (1) Take up land which can be used for crops (1)
What are the nine types of energy?
Kinetic, sound, light, thermal, electrical, gravitational potential, elastic potential, chemical, nuclear
What is ‘wasted energy’?
Energy that is transformed to either the wrong place or the wrong form
What is ‘useful energy’?
The energy transformed to where it is wanted in the form wanted
If energy can not be created or destroyed why are we concerned with waster energy?
A lot of energy is wasted as thermal which dissipated and spreads out to the surroundings. This energy becomes so spread out it can’t be reused usefully again.
What is the equation for work done?
Work done = force x distance in direction of force
What is the relationship between work done and energy transferred
Work done = energy transferred
