physics revision Flashcards
what are the two types of waves?
transverse and longitudional
what are the electromagnetic waves?
radio waves, microwaves, infrared waves, visible waves, ultraviolet waves, x-rays and gamma rays
conduction of heat is where vibrating particles pass on their kinetic energy to another particle. true or false?
true
do hot air particles rise or fall?
rise
what does an ammeter measure?
amps
what does a volt meter measure?
volts
how do you fix drafts in a house?
double glazed windows, loft insulation, carpets, cavity wall insulation, draft excluders.
what is the most dense, solid, liquid or gas?
solid
how do you find the density of a irregular stone?
drop in water and measure the rise.
how does conduction work?
the particles in the solid vibrate and transfer the kinetic + heat energy towards the particles in the other solid.
how does convection work?
the hot air rises and the cold air falls causing a convection current.
what can travel through a vaccum?
radiation only.
what does VIR stand for.
voltage, current and resistance.
what do you need to do to find the resistance of a component.
know the current and the voltage, then divide the voltage by the current.
Ω - what is this
an ohm.
will the current turn towards the easiest route with the least resistance?
yes
what is an LDR?
light dependant resistor.
what is the power triangle.
power = energy transfered / time (or any version of this)
what is watts
a unit of power
what does an earth wire do?
keeps everything safe.
is current the same or different in a series circuit?
same
is current the same or different in a parallel circuit?
different
what is in the national grid?
powerstation, step up transformer, pylons, step down transformer, home or buisness.
what is the voltage of the parts of the national grid?
25000 powerstation, 400000 pylons, 230 home
what is a kWh?
kilowatt hour.
how do you calculate energy transfered?
power * time
what are fuses used for?
if too much voltage goes through a fuse it melts as they have low melting points.
what colours are the wires ina plug?
brown for live wire, green and yellow for earth wire and blue for neutral wire.
define mcb.
miniature circuit breaker breaks a section of a circuit by seperating peices of metal and breaking the circuit.
what is the earth wire for?
to protect apliances from having too much voltage flowing through.
what does the angle of incidence entail?
most of the light gets reflected
what is the critical angle?
the angle upon where the light refracts against the boundary line.
what is total internal reflection?
where all light is reflected equally from the boundary.
