Terms : Hide Images
| 16302709731 | Energy stores | Thermal, kinetic, gravitational potential, elastic potential, chemical, magnetic, electrostatic, nuclear | 0 | |
| 16302709732 | Closed system | A system where neither matter nor energy can enter or leave. The net change in the total energy of this system is always 0 | 1 | |
| 16302709733 | Energy transferred by heating | Example: kettle Energy is transferred to the water, from the kettles heating system(water), by heating, into the waters thermal energy store. Causing the temperature to rise | 2 | |
| 16302709734 | Work done | force x distance | 3 | |
| 16302709735 | Energy lost from the gravitational potential energy store | = Energy gained in the kinetic energy store | 4 | |
| 16302709736 | Kinetic energy (Ek) = | 1/2 x mass(kg) x speed(m/s)*2 | 5 | |
| 16302709737 | Gravitational potential energy (Ep) = | mass(kg) x gravitational field strength(N/kg) x height(m) | 6 | |
| 16302709738 | Joules | unit of energy | 7 | |
| 16302709739 | Elastic potential energy (Ee) = | 1/2 x spring constant (N/m) x extension(m)*2 | 8 | |
| 16302709740 | Specific heat capacity | The amount of energy needed to raise the temperature of 1kg of a substance by 1° | 9 | |
| 16302709741 | Change in thermal energy (E) = | Mass(kg) x specific heat capacity(j/kg°C) x temperature change(°C) | 10 | |
| 16302709742 | Specific heat capacity practical | 1. Block of investigation material with 2 holes in it, for the heater and thermometer 2. Measure mass of the block then wrap in an insulating layer, to reduce energy transferred to surroundings, insert therm and heater 3. Measure blocks initial temp and set the potential difference of power supply to 10V, turn on and start stopwatch 4. The current does work on the heater, transferring energy electrically from power to heaters thermal energy store. The energy is then transferred to materials thermal energy store by heating. 5. As block heats up, use thermometer to measure it's temp every minute, current shouldn't change 6. Using your measurements you can calculate power and transfer | 11 | |
| 16302709743 | Conservation of energy | Energy can be transferred usefully, stored or dissipated, but can never be created or destroyed | 12 | |
| 16302709744 | Dissipated energy | Sometimes called 'wasted energy' because the energy is being stored in a ways that is not useful | 13 | |
| 16302709745 | Watts | unit for power | 14 | |
| 16302709746 | Power = | Energy transferred / time | 15 | |
| 16302709747 | Power = | Work done / time | 16 | |
| 16302709748 | Conduction | The process where vibrating particles transfer energy to neighbouring particles | 17 | |
| 16302709749 | Convection | The process where energetic particles move away from hotter to cooler regions | 18 | |
| 16302709750 | Lubrication | Lubricants can be used to reduce friction between objects surfaces when they move. This stops transfer of energy to useless stores | 19 | |
| 16302709751 | Insulation | - Cavity walls : reduces energy transferred by convection and conduction - Loft insulation : fibreglass wool used, reduces energy lost by conduction - Double glazed windows : prevents energy transfer by conduction - Draught excluders : reduces energy transferred by convection | 20 | |
| 16302709752 | Efficiency | Useful output energy transfer / total input energy transfer | 21 | |
| 16302709753 | Non-renewable energy resources | Fossil fuels and nuclear, Coal,oil,gas | 22 | |
| 16302709754 | Renewable energy resources | Solar, wind, water waves, hydroelectric, bio-fuel, tidal, geothermal | 23 | |
| 16302709755 | Wind power | -Turbine with generator, rotating blades turn the generator and produce electricity -No pollution, spoil the scenery, very noisy, sometimes no wind, initial costs quite high, no permanent environment damage | 24 | |
| 16302709756 | Solar power | - Generate electric currents directly from sunlight -No pollution, only reliable in daytime, can't increase power output when there's more demand, initial cost is high | 25 | |
| 16302709757 | Geothermal power | -Uses underground thermal energy stores, slow decay of various radioactive elements -Free energy, used to generate electricity or heat buildings directly, not enough suitable locations, cost of building is high | 26 | |
| 16302709758 | Hydroelectric power | -Transfers energy from kinetic store of falling water -No pollution, flooding of valley, loss of habitat, unsightly, reliable, initial costs high | 27 | |
| 16302709759 | Wave power | -Wave-powered turbines located around the coast -No pollution, disturbs marine habitats, hazard to boats, unreliable, initial cost is high | 28 | |
| 16302812472 | Tidal power | -Big damn built across river estuaries with turbines in them. Water allowed out of estuary through turbines at controlled speed -No pollution, spoils view, habitats destroyed,reliable | 29 | |
| 16302901340 | Bio-fuels | -Created from either plant products or animal dung. They can be solid, liquid or gas and burnt to produce electricity or run cars -Carbon neutral,reliable,cost to refine them is high,large forests cleared | 30 | |
| 16302981098 | Resistance | The greater the resistance across a component, the smaller the current that flows through it | 31 | |
| 16303054255 | Charge = | current x time | 32 | |
| 16303086082 | Bulb |  | 33 | |
| 16303105496 | Fuse |  | 34 | |
| 16303113699 | LED |  | 35 | |
| 16303121838 | Resistor |  | 36 | |
| 16303133321 | Variable resistor |  | 37 | |
| 16303140094 | Ammeter |  | 38 | |
| 16303150911 | Voltmeter |  | 39 | |
| 16303161434 | Diode |  | 40 | |
| 16303177912 | LDR | -Dependent on intensity of light -Bright light, resistance falls |  | 41 |
| 16303188603 | Thermistor | -Temp dependent resistor -Hot conditions, resistance drops |  | 42 |
| 16303207742 | Potential difference = | current x resistance | 43 | |
| 16303225461 | Resistance practical | 1. Attach a crocodile clip to the wire level with 0cm on the ruler 2. Attach 2nd crocodile clip, 10 cm away from first clip, write down the length between 3. Close the switch then record the current through the wire and pd across it 4. Repeat for a number of different lengths 5.Calculate all lengths resistances |  | 44 |
| 16303349709 | Ohmic conductor (resistor) graph | Directly proportional |  | 45 |
| 16303373689 | Filament lamp graph | As current increases, temp increases so resistance increases. Means less current can flow through pd unit |  | 46 |
| 16303399965 | Diode graph | Current will only flow through in one direction, diode has high resistance in other direction |  | 47 |
| 16303491771 | Series circuits | -Potential difference is shared -Current is the same everywhere | 48 | |
| 16303564230 | Parallel circuits | -Potential difference is the same across all components -Current is shared between branches -If 2 resistors, total resistance is less than resistance of the smallest resistor | 49 | |
| 16304448377 | Neutral wire | -Blue --Carries away current -Electric flows out of this wire |  | 50 |
| 16304477165 | Live wire | -Brown -Provides the alternating potential difference from the mains supply -Electricity flows in through this wire | 51 | |
| 16304520846 | Earth wire | -Green and yellow -Protects the wiring and for safety -Stops appliance casing from becoming live | 52 | |
| 16304584002 | Energy transferred = | Power x time | 53 | |
| 16304602594 | Energy transferred = | Charge flow x potential difference | 54 | |
| 16304628706 | Power = | Potential difference x current | 55 | |
| 16304663220 | National grid | -Uses high pd and low current -Step up transformer increases pd for efficient transmission -Step down transformer decreases pd for safe and usable levels -Big pylons have huge insulators |  | 56 |
| 16304759524 | Density = | mass/volume | 57 | |
| 16304776028 | Density of an object practical | 1. Measure object's mass 2. Submerge it in a eureka can filled with water 3. Water displaced by object will be transferred to measuring cylinder 4. Record volume of water. This is volume of the object. 5. Put it in formula to find density | 58 | |
| 16304838338 | Density of a liquid practical | 1. Place a measuring cylinder on a balance and zero the balance 2. Pour 10ml of liquid into measuring cylinder and record liquid mass 3. Pour another 10 ml in and record total volume and mass. Repeat until cylinder is full 4. Use density formula for each measurement 5. Take an average of calculated densities | 59 | |
| 16304906579 | Internal energy | the sum of the kinetic and potential energies of all particles in the system | 60 | |
| 16304967429 | Specific latent heat | Amount of heat needed to change the state of 1 kilo of a substance WITHOUT a change in temperature. | 61 | |
| 16304984564 | Specific latent heat of fusion | The specific latent heat for change between a solid and a liquid. | 62 | |
| 16304993130 | Specific latent heat of vaporisation | The specific latent heat for change between a liquid and a gas. | 63 | |
| 16304999420 | Energy = | mass x specific latent heat | 64 | |
| 16305044316 | Plum pudding model | J.J Thomsons model of an atom, in which he thought electrons were randomly distributed within a positively charged cloud | 65 | |
| 16305064416 | Alpha scattering experiment | In this experiment Rutherford shot alpha particles through a thin sheet of gold and discovered nucleus with positive charge | 66 | |
| 16305112006 | Bohr | Says that electrons move in circular/definite orbits around the nucleus in energy levels at certain distances from nucleus | 67 | |
| 16305122879 | Chadwick | Discovered the neutron | 68 | |
| 16305147305 | Isotopes | Atoms of the same element that have different numbers of neutrons | 69 | |
| 16305154975 | Alpha particle | -2 neutrons and 2 protons -Can only travel few cm and absorbed by sheet of paper -Strongly ionising -Used in smoke detectors | 70 | |
| 16305328374 | Beta particles | -Fast moving electron -Moderately ionising -Can travel a few metres and absorbed by sheet of aluminium | 71 | |
| 16305374191 | Gamma rays | -Electromagnetic radiation released by nucleus -Travel long distance and penetrate far into materials -Weakly ionising -Absorbed by thick sheets of lead or concrete | 72 | |
| 16305450861 | Alpha decay | A nuclear reaction in which an atom emits an alpha particle consisting of two protons and two neutrons. This decreases the atomic number by 2 and the mass number by 4. | 73 | |
| 16305513136 | Beta decay | radioactive decay of an atomic nucleus, 1 proton gained 1 neutron lost | 74 | |
| 16305587185 | Half-life | the time taken for the radioactivity of a specified isotope to fall to half its original value. | 75 | |
| 16305638137 | Irradiation | exposure to any form of radiant energy such as light, heat, or x-rays | 76 | |
| 16305653240 | Contamination | Unwanted radioactive atoms get onto or into an object, atoms might decay releasing radiation that may cause you harm | 77 |
