What colours on a thermogram represent hot temperatures?
White
Blue
Yellow
Red
Black
Purple
Define: Temperature
= a measurement of energy on an absolute scale.
= a measurement of the average kinetic energy of particles.
= total energy of all particles.
Thermal energy always flows from a hotter area to a cooler one.
What is the equation for specific heat capacity?
energy / (mass x temperature change)
energy / mass
When a substance melts or solidifies there is no temperature change.
The kinetic energy of particles increases at colder temperatures.
What does arrow A on this graph showing changes of states represent?
Melting
Boiling
Freezing
Condensing
What does arrow B on the graph showing the changes of state of water represent?
What are the 3 types of thermal transfer?
Conduction
Radiation
Nuclear
Convection
Sun
Conduction can work in solids because the particles pass their energy to neighbouring particles.
Warmer regions of a fluid are more dense than cooler regions of fluid.
What 2 surfaces are the best for absorbing and emitting radiation?
Shiny
Matt
Silver
Which of the options below are methods of insulation?
Curtains and draught excluders
Cavity walls
Double glazing
Carpets and underfloor insulation
Reflective foil behind radiators
What is this a diagram showing?
Energy flow
Wasted energy
Efficiency
Useful energy
The higher the efficiency the less energy is wasted.
If you put ice cubes in a glass, why do they melt?
The ice cubes cool the surroundings.
The surroundings transfer heat to the ice cubes.
The ice cubes need to be kept in the freezer.
What is the definition of a wave?
The transfer of energy without the transfer of matter.
The movement of energy through water.
The movement of particles in any surface/object.
The definition of a longitudinal wave is...
...when the displacement is perpendicular to the direction of the wave.
...when the displacement is parallel to the direction of the wave.
Define: Frequency
= the number of complete waves to pass a point in 1 second.
= the time taken for one wave to pass a point.
Light travels in straight lines.
In the reflection of light, the angle of incidence is greater than the angle of reflection.
How does the speed of light change when it enters a denser material?
It speeds up
It slows down
It doesn't change
It stops
In refraction, the emergent ray bends towards the normal.
Define: Diffraction
= the bending of light.
= the bending of waves through a hole or around an obstacle.
= the trajectory of a wave.
Which of the 3 statements below are true about ionising waves?
They have a severe effect on living tissue by killing cells or damaging DNA.
They are harmless to humans.
They have a short wavelength and high frequency.
They carry lots of energy.
They have a long wavelength and low frequency.
What is the order of the waves in the electromagnetic spectrum? (starting with highest frequency and shortest wavelength)
X-Ray, Ultraviolet, Visible, Infrared, Microwaves, Gamma, Radio waves
Gamma, X-Ray, Ultraviolet, Visible, Infrared, Microwaves, Radio waves
Gamma, Ultraviolet, Visible, X-Ray, Infrared, Microwaves, Radio waves
Radio waves, Gamma, X-Ray, Visible, Infrared, Ultraviolet, Microwaves,
Which of the following are uses of gamma waves?
Tanning Machines
Treating cancer
TV remote
Sterilising medical instruments
Seeing bones
Select the 3 properties off Infrared waves.
They can burn human tissue by transferring their energy to our skin.
They are reflected by metal surfaces.
They can't penetrate materials such as plastic and glass.
They can pass through glass and plastic.
Infrared waves are absorbed by food during cooking.
How does a microwave oven cook food?
The fan reflects waves from the turbine. They fill the oven and cook the food.
The fan reflects waves from the generator. They bounce off the walls and cook the food.
The fan reflects waves from the magnetron. They reflect off the walls and cook the food.
What is the critical angle of glass?
40 degrees
41 degrees
42 degrees
What is one benefit for patients when using an endoscope?
Patients will have a quicker recovery time as the surgery is less intrusive so no risk of infection.
The operation hurts less.
The doctor doesn't have to use a knife.
What are the 2 methods that can be used for multiplexing?
Different colours
Different sizes
Different times
Different divisions
An analogue signal varies continuously in amplitude and frequency.
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