Fichas
GCSE Physics 2b
Fichas del conjunto (16)
- 1An AC supply of electricity has a time period of 0.08s. What is the frequency?1/0.08 = 12.5
- 2What are the three wires in the three pin plug? What does each one do?Live - alternates between a positive and negative high voltage
Earth - Carries electricity to the earth if something is wrong
Neutral - always neutral - 3How do the fuse and the earth wire work together?FAULT develops in the wire
SURGE in current melts fuse, cutting off the live supply and breaking the circuit
ISOLATES the whole appliance so you can't get an electric shock
ALSO prevents the risk of fire
FSIA - 4How does an RCCB work?It detects the difference in current and cuts off the power by opening a switch.
Quicker than fuses and can be reused - 5What are the relative masses and charge of the 3 basic subatomic particles?Particle mass charge
Proton 1 +1
Electon 0 -1
Neutron 1 0 - 6What is an alpha particle?2 protons, 2 neutrons
Overall positive charge
Good at ionising
Bad at penetrating - 7What is a beta particle?1 electron
Overall negative charge
Moderate at ionising
Moderate at penetrating - 8What is a gamma ray?An electromagnetic wave
No charge
Bad at ionising
Good at penetrating - 9List two places where background radiation is increasedIn coastal areas where there are lots of rocks
Man made sources eg from nuclear weapons and nuclear waste - 10What occupations have an increased risk of exposure to radiation?Commercial pilots
Miners
Nuclear industry workers
Radiographers - 11What is the definition of half life?Half life is the life taken for the number of nuclei in a radioactive sample (isotope) to halve.
- 12Give an example of how gamma radiation can be used in medicineIn radiotherapy for cancer patients as it has a short half life, so kills the cancer cells without the patient being radioactive for too long
- 13What materials can stop alpha, beta and gamma rays?Alpha- paper (large so stopped easily)
Beta- Aluminium
Gamma- concrete or lead (very small) - 14What is the main environmental problem associated with nuclear power?Often uses more energy than it releases
- 15Give the main stages of the life cycle of a star around THE SAME size of our sun1) Protostar
2) Main sequence star
3) Red giant
4) White dwarf
5) Black dwarf - 16Give the main stages of the life cycle of a star much BIGGER than our sun1) Protostar
2) Main sequence star
3) Super red giant
4) Supernova
5) Neutron star OR black hole