Physics 1b Flashcards
(23 cards)
List some renewable energy sources
Wind, waves, tides, hydroelectric, solar, geothermal, food, biofuels
List some non renewable energy sources
Coal, oil, gas, nuclear fuels
How do pumped storage systems work?
Spare night time electricity is used to pump water up a reservoir which can then be released quickly when extra electricity is needed
What are biofuels?
Organic matter that can be burnt to release energy
Why are step up transformers used?
To increase voltage but reduce current to reduce energy loss through heat
What is a transverse wave?
Where the vibrations are perpendicular to the direction of energy transfer of the wave
What is a longitudinal wave?
Where vibrations are parallel to the direction of energy transfer of the wave
How do you calculate wave speed?
Frequency * wavelength
Angle of incidence=?
Angle of reflection
What is diffraction?
When waves spread out at the edges when they pass through a gap. The narrower the gap, the wider the diffraction.
What is refraction?
When a wave changes direction when it crosses a boundary between two substances e.g. From glass to air.
Give some examples of transverse waves
Light, EM waves, ripples in water
Give some examples of longitudinal waves
Sound
List the different types of waves on the electromagnetic spectrum in order
Radio, micro, infra red, visible, ultra violet, x rays, gamma rays
How are radio wave received if the receiver isn’t in the line of sight of the transmitter
The diffraction effect. Long wave radio wavelengths diffract around hills
How are short wave signals received at long distances?
They are reflected from the ionosphere
What are microwaves used for?
Satellite communication and mobile phones
Why are microwaves used in satellite communications?
Unlike radio waves, they can pass through the earths watery atmosphere into space.
What are infrared waves used for?
Remote controls and optical fibres
What type of wave is a sound wave?
Mechanical longitudinal
How does the frequency of a sound wave affect the pitch?
The higher the frequency the higher the pitch
What is an echo?
A reflected sound wave
describe the steady state theory of the universe
The universe has always existed at is is now and always will
