GCSE Flashcards
Describe the characteristics of alpha particles and beta particles in terms of their deflection in an electric field.
beta particles have a smaller mass so are deflected more than alpha particles
beta particles have a smaller mass than alpha but alpha particles have a greater charge than beta
alpha particles and beta particles are deflected in opposite directions in
an electric field
The braking distance of the car depends on the speed of the car.
For the same braking force, explain what happens to the braking distance if the
speed doubles.
You should refer to kinetic energy in your answer.
if speed doubles then KE increase by a factor of 4
work done to stop the car increases by a factor of 4
work done = force x distance but force is constant
so if work done increases by a factor of 4, distance increases by a factor of 4
Advantages of turning off electrical appliances not in use:
less fossil fuels burned
less greenhouse gases produced conserve fossil fuels
If energy is not usefully transferred it is…
wasted
What fossil fuel power station has the shortest start up time?
gas (already in a state to turn a turbine)
What forms the National Grid?
cables and transformers
Why would you be waiting for something (e.g. wait 20 seconds after turning on fan)
so that it reaches a steady/same speed/temperature etc
How would you increase evaporation?
- temperature increase
- less humid
- more windy (wind carries water vapour which dries the air)
Charge can only flow if there is… which means current can only flow if there is a….
potential difference
Resistance
opposes/slows down flow of charge
Potential difference is the…
driving force that pushes the charge around
Direct current
current that always flows in the same direction
If three resistors are identical in a series circuit then the p.d. of each resistor must be…
1/3 of the cells p.d.
The voltmeter is always in…
parallel
Why should you switch off the circuit?
to prevent the wire/resistor from getting hot
which would increase the resistance
How does a fuse work?
if current is above the value of the fuse
fuse melts
breaks circuit
How can you can get an electric shock touching a car?
charge builds up on the metal frame of the car so when you touch it you complete the circuit and it flows through you to the earth (as you are 0V)
Why may the conclusion not be correct for all types of objects (e.g. fridges)?
small number sampled`
Why shouldn’t you work with electrical appliances without turning off the mains?
can get an electric shock
if live wire is touched
Static electricity between cloth and rod.
when rubbing the cloth on the rod, the friction causes electrons to move from rod to cloth.
rod loses electrons and cloth gains electrons
rod gains a positive charge, cloth gains a negative charge
Materials in which electricity passes straight through are called…
conductors
An electric shock is caused by
the build-up of charge
Materials in which electricity is inhibited from passing through are called…
insulators
What happens to the charge on a rod when you rub it with your hands?
it is lost to the earth/body
