p1
Heating/radiation
Electrical
Mechanical
What do Coulombs measure
Charge
What is Internal Energy
Total Potential and Kinetic energies of all particles in a substance.
What is a Becquerel and what is a Sievert
Becquerel is the rate of decay and Sieverts are the measure of radiation dose
What is a risk in the specific heat capacity practical
Hot metal block and induction heater
Conservation of energy (full description)
Energy cannot be created or destroyed, only transferred from one store to another
Alternating and Direct current
AC- Current and potential difference change direction constantly
DC- Current only flows in one direction
What is Boyle's Law
Pressure is inversely proportional to volume
What is Half life.
The time taken for half of the unstable nuclei in a source to have fully decayed and become stable or for the count rate to half
Suggest 2 independent variables for the thermal insulation practical
layers/thickness of insulation or material of insulation
5 types of energy store
Chemical
Kinetic
Gravitational potential
Elastic Potential
Internal
Nuclear
Magnets
Electrostatic
Potential difference, current and resistance rules for series and parallel
Series: current is the same everywhere, potential difference of the cell is split across all components, Rtotal=R1+R2...
Parallel: current splits at branches, potential difference across the cell is the same as the total potential difference on each branch, resistance is smaller than that of the smallest resistor.
Describe how energy stores of a substance increase as it turns from a solid, then to a liquid and to a gas.
Changing state- energy goes to potential energy store in order to break bonds
Increasing Temperature- Kinetic energy increases
How do energy levels work.
Electron absorbs EM radiation
Becomes excited and jumps up energy levels
Looses energy by emitting electromagnetic waves and jumping down energy levels
What 2 components could be used to measure resistance of a resistance wire
Ammeter and Voltmeter
2 ways to reduce dissipation
Insulation and Lubrication
Describe the IR graphs for a filament bulb, diode and ohmic resistor
Ohmic resistor- potential difference and current are always directly proportional
Filament bulb- temp increases so resistance does too, reducing the current
Diode/LED- no current or potential difference in negative direction because of a very high resistance.
Definition of Specific Heat Capacity and Specific Latent heat
Specific Heat Capacity is the energy needed to heat 1kg of a substance by 1 degree celsius.
Specific Latent Heat is the energy needed to change state of 1kg of a substance
Why is contamination more dangerous than Irradiation
Harder to remove, can't be shielded, ionizes more (alpha particles) and makes you radioactive
What electrical component should you not use a high potential difference on.
Diode or LED
Name 4 types of renewable energy, give one disadvantage for each
For example:
Wind- takes up lots of space
Hydroelectric- destroys habitats
Biofuel- Carbon neutral and creates monocultures
Geothermal- Fluids drawn up from the ground contain carbon dioxide and methane
Describe all wire's positions, colours, uses and names inside a socket plug
Live- Brown- Bottom right. Supplies current at 230V and 50Hz
Neutral- blue- bottom left. Takes current away and completes the circuit
Earth- yellow and green- top. 0V grounds the appliance so that is the live wire comes loose, current is taken through the earth wire into the ground, instead of into a person/electrocution
Types of radiation
Alpha- short 5cm range- absorbed by paper and skin (not very penetrative), very highly ionizing, made of 2 protons and 2 neutrons. Shown as 42He2+
Beta- medium 1m range- absorbed by 5mm of aluminum, medium ionizing, single electron
Gamma- unlimited range- stopped by several cm of lead, low ionizing, EM wave
Nuclear Fission
Uranium nucleus absorbs a slow moving neutron
Nucleus splits into 2 smaller daughter nuclei
1-3 neutrons are released that cause chain fission events
Control rods can be lowered to absorb extra neutrons to prevent an atomic bomb
How could I find the density of my lucky rock
(eureka can practical)