Download P1 revision fact sheet missing words

Physics 1 revision facts
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Heat energy moves from a h…………………. object to c…………………. surroundings
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Heat energy is transferred in one of 3 ways
- c…………………. ….. – vibrating particles pass on their energy to the particles
next to them. The main form of heat transfer in solids
- c…………………. ….. – particles with the most energy move from the hotter
place to the cooler place and take their heat energy with them. The main form of
heat transfer in liquids and gases.
- r………………….….. is the transfer of heat energy by electromagnetic waves
and occurs in solids, liquids and gases
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The bigger the t…………………. ….. d…………………. ….. the faster heat is transferred
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All objects are continually e…………………. ….. and a…………………. ….. heat radiation
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The b…………………. ….. the surface area the more w…………………. ….. can be emitted
from the surface so the q…………………. ….. the transfer of heat
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Radiation depends on surface c…………………. ….. and t…………………. …..
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D……….….. m……….….. surfaces absorb heat much better than bright glossy surfaces
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S………………….….. surfaces r………………….….. nearly all radiation falling on them
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Conduction of heat is the process where vibrating particles pass on their extra
k………………….energy to neighbouring particles
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M………………….….. are good conductors because they have free e………………….…..,
which can move through the object and transfer heat
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Convection occurs when the more energetic particles move from the
h………………….….. region to the c………………….….. region and take their heat energy
with them.
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Convection currents are all about changes in d………………….…... Hot water/air is
l…………….. dense. Less dense water/air r………….….. and cool water/air is more dense
and sinks
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K………………….….. theory explains the 3 states of matter.
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The particles in a s………………….….. are tightly packed together with strong forces of
a………………….….., unable to move but can v………………….….. around a fixed point.
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The particles in a l………………….….. are still packed together, but with weaker forces
of attraction, can move past each other at l………………….….. speeds.
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The particles in a gas are spaced out, almost n……… forces of attraction, free to move
in any direction at high speeds.
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Condensation is a g…………… turning into a l………. As the gas cools the particles slow
down and lose e…………………. The attractive forces pull them c………………….….
together so the gas becomes a liquid
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The rate of condensation will be faster if
 the surface temperature of the liquid is l………………….…..
 the surface area of the liquid is l………………….…...
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E………………….….. is a liquid turning into a gas. As the particles at the surface of the
liquid heat up and gain energy they can escape.
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The rate of evaporation will be faster if
 temperature of the liquid is h………………….…..
 the density of the liquid is ………………….…..
 the surface area of the liquid is l………………….…..
 the airflow over the liquid is g………………….…...
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The rate an object transfers heat energy depends on
 S………………….….. area – the bigger the surface area the more infrared waves can
be emitted = faster rate of transfer
 V………………….….. – the smaller the volume the faster the rate of transfer
 M………………….….. – conductors transfer at a faster rate, darker matt surfaces
transfer at a faster rate
 T………………….….. difference – the bigger the temperature difference the faster
the rate
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Vacuum flasks are designed to reduce heat transfer
 Plastic cap – reduces c………………….…..
 Plastic casing – reduces c………………….…..
 Shiny silver insides – r………………….….. heat back onto liquid
 Double glass wall, filled with air – stops c………………….….. and c………………….…..
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Insulation reduces heat loss from homes
 Loft insulation – reduces c………………….….. and r………………….…..
 Cavity wall insulation – reduces c………………….….. and r………………….…..
 Hot water tank jacket – reduces c………………….….. and r………………….…..
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P………………….….. time = initial cost of insulation / annual saving
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U-values show how fast heat is transferred through a material
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The h………………….….. the value, the f………………….….. the heat transfer
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The better the i………………….….. the l………………….….. the U-value
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S………………….….. heat capacity is the amount of energy needed to raise the
temperature of 1kg of a substance by 1oC.
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Specific heat capacity can be calculated by (DON’T NEED TO LEARN)
Energy transferred (J) = mass (kg) x specific heat capacity (J/kgoC) x temp change (oC)
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There are 9 types of energy – e………………….…..; light; s………………….…..; kinetic;
nuclear; t………………….…..; gravitational potential; elastic potential; c………………….…..
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Potential and chemical are forms of s………………….….. energy
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Energy can never be c………………….….. or d………………….….. it can only be converted
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Energy is only useful when it is converted from one form to another
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Energy transfers involve losses often as h………………….…..
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The efficiency of any device is defined as
useful energy output / total energy input
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Efficiency is usually given as a p………………….…..
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No device is 100% efficient and the wasted energy is always as heat.
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All types of energy are measured as J………………….….. (J)
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Electrical devices convert e………………….….. energy into heat, sound, light etc.
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Batteries convert chemical energy into electrical energy to run devices
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Electrical generations always involves converting other forms of energy into
electrical energy
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Gravitational and elastic potential energy always get converted into kinetic energy
first
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The units of energy are K………………….….. -h………………….….. (kW-h)
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A kilowatt-hour is the amount of electrical energy used by a 1kW appliance left on
for 1 hour
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Energy = p………………….….. x t………………….…..
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Energy is measured in joules and power is measured in w………………….…..
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Number of units (kW-h) used = p………………….….. (kW) x time (hours)
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Cost = number of units x price of units
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N……-R………………….….. energy resources will run out one day. These are
c………………….….., oil, g………………….….. and nuclear fuels.
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Coal, oil and gas are burnt in a power station to heat water, to produce steam. The
steam turns a t…………………..., which turns a g…………………. which produces electricity.
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All 3 fossil fuels release c………………….….. d………………….…... Burning coal and oil
releases s………………….….. d………………….…... These both cause pollution, and can
cause global w………………….….., a………… r………………… and climate changes
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Nuclear reactors use nuclear fission to heat the water to produce the steam, to turn
the turbine, to turn the generator.
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There is no p………………….….. as nothing is being burnt.
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Renewable energy resources will never run out. They are w…………, wave, tides,
h………………….….., s………………….….., geothermal, food, biomass.
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These resources are designed to turn the turbines directly, which turns the generator
to produce electricity.
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They damage the environment less than non-renewable, but don’t provide as much
e………………….…..
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Electricity gets around via the n………………….….. g………………….…..
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Electricity is carried at very high v…………….….. and low c………………… as it is cheaper
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The voltage used is 4………………….V. It requires t………………….….. and large pylons to
carry the electricity at this voltage
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Transformers alter the v………………….. They step it up (i………………….….. it) at one end
and step it down (l………………….….. it ) at the other.
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Electromagnetic waves carry e………………….….. not m………………….…..
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W………………….….. is the distance from the peak of one wave to the peak of the next
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F………………….….. is how many complete waves there are per second. Measured in
h………………….…... 1 Hz is 1 waves per second
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A………………….….. is the height of the wave from the midline to the peak
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W………………….….. is how fast the wave travels
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In transverse waves the vibrations travel at ……… to the direction of energy transfer
of the wave
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Most waves are transverse e.g. l……….….. and e………………….….. waves
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In longitudinal waves the vibrations are p………………….….. to the direction of energy
transfer of the wave.
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Sound waves and u………………….….. are examples of longitudinal waves
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Wavespeed (m/s) = f………………….….. (Hz) x w………………….….. (m)
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Reflection of light allows us to see objects
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Light travels in s………………….….. lines
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The n………………….….. is a line drawn at 90o to a surface
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Angle of i………………….….. = angle of r………………….…..
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An image formed in a plane mirror is
 Same s………………… as the object
 Same d………………….….. from the mirror as the object
 V………………….….. (appears to be coming from a different place)
 U………………….…..
 Laterally i………………….…..
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D………………….….. is the spreading out of waves. This happens if a wave passes
through a gap.
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The amount of diffraction depends on the size of the gap
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The n………………….….. the gap, or the l………………….….. the wavelength, the more the
wave spreads out
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R………………….….. is the bending of a wave due to a change in medium
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As light passes from a l…………… dense medium into a m……. dense medium (e.g. air
into glass) the light ray bends t………………….….. the normal
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As light passes from a more dense medium into a less dense medium (e.g glass into
air) the light ray bends a………………….….. from the normal
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The electromagnetic spectrum is made up of
R……………
Microwaves
I……………… Visible light
U……………
X-rays
Gamma rays
Low f………………….…..
High frequency
Long wavelength
S……… wavelength
Low energy
High energy
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EM radiation can be a………………….….., r………………….….. or t………………….…..
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When it is absorbed it can make the object h………………….….. or set up an tiny
alternating current with the same frequency as the EM wave
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Radiowaves can pass through soft tissue without being a………………….…..
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Microwaves are absorbed and cause the cells to heat up
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UV rays can cause skin c………………….…..
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Radiowaves are used for c………………….…..
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Microwaves are used for s………………….….. communications and in m…………… phones
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O………………….….. fibres use visible light and infrared
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UV is used in s………………….….. and fluorescent light tubes
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X-rays are used in h………………….…..
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Sound travels as a w………………….
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Sound is caused by v………………….….. objects. These vibrations are passed through
surrounding mediums as a series of compressions
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The sound eventually travels to someone’s ear
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Sound cannot travel in a v………………….….. (no particles)
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Humans can hear sounds with a frequency between 2………..-2………………Hz
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Sound waves can reflect and refract
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E………………….….. are r………………….….. sound waves. There will be a delay between
the original sound and the echo as the sound has further to travel.
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H………………….….. frequency sounds have high pitches
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Low frequency sounds have l………………….….. pitches
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The Universe began with the B……….. B…………… – an explosion which occurred from
a single space. The universe then started expanding and still is.
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C………………….….. M………………….….. B………………….….. R………………….….. (CMBR) is
low frequency electromagnetic radiation with was thrown out during the Big Bang –
proof of it happening.
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R………………….….. s………………….….. is more proof that the Big Bang occurred.
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Light from d………………….….. galaxies are at a lower frequencies than they should be.
It is shifted towards the red end of the visible spectrum. The f………………….….. away a
galaxy is the bigger the red shift.
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This means the more distant galaxies are moving away from us f………………….….. than
nearer ones
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This provides the evidence that the Universe is e………………….….. and supports the big
bang theory
.