Flashcards
P1 Part 2
Cards in this deck (29)
- 1What is a renewable energy resource?One that will not run out
Examples include; Solar, Wave, Tidal, Geothermal, Wind - 2What is a biofuel?It is a renewable fuel that comes from a biological source. E.g. chicken litter, methanol, ethanol
- 3What is carbon-neutral?A term applied to a fuel which when burnt only releases CO2 into the atmosphere that it had absorbed in its lifetime.
- 4How does NUCLEAR power work?Energy from radioactive decay
Heats up water into steam
Steam turns turbine
Turbine turns generator - 5How does a COAL power station work?Coal is burnt
Heats up water into steam
Steam turns turbine
Turbine turns generator - 6What are the ENERGY changes in a HEP station? (Dam)Gravitational to Kinetic
Kinetic to Electrical - 7How can we reduce CO2 emissions from power plants?Use CCS (carbon capture & storage) technology – e.g. pumping under the sea into caverns where oil & gas originally came from
- 8What are some of the advantages & disadvantages of wind turbines?☺: No CO2 emissions in use, free “fuel”
☹: Unreliable (not always windy), Eyesore - 9What is pumped storage?Where excess electricity is used to pump water back up to the top of a Dam so that it can be used again in times of peak demand
- 10How does the national grid work?Step-up transformer to increase Voltage and decrease current
So that electricity through the wires/pylon system is at LOW current
To reduce losses through heating of the wires
Step-down transformer to decrease the Voltage ready for use at the other end - 11What are the advantages & disadvantages of overground & underground wires?Underground: Less risk of electrocution, Expensive to install & repair
Overground: Cheap to install & repair, Can be affected by extreme weather (e.g. storms) - 12What are the start-up times of different power plants?Nuclear (longest), Coal, Oil, Gas, Hydroelectric (shortest)
- 13How is the variable demand for electricity met?Bigger power stations and ones with longest start-up time used to meet the Baseload
This is topped up with additional capacity from powerstations with shorter start-up times (e.g. gas)
Spikes are met by using HEP - 14What is a wave?Oscillation
Which transfers energy (not matter)
E.g. mechanical: Earthquake, Water waves, Sound
E.g. Electromagnetic: Light, Microwave - 15What is a transverse wave?Oscillations are perpendicular to direction of energy transfer
E.g. Light
Amplitude/Wavelength (m)/Frequency (Hz) - 16What is a longitudinal wave?Oscillations are parallel to the direction of energy transfer
E.g. Sound
Waves travel as alternating compressions & rarefactions - 17How is the speed of a wave calculated?Wavespeed (m/s) = Frequency (Hz) x Wavelength (m)
Frequency = Wavespeed / Wavelength
Wavelength = Wavespeed / Frequency - 18What are the rules of reflection?Angle of incidence = Angle of reflection
Images formed in a mirror are VIRTUAL as real light rays do not cross to make the image
(always draw 2 rays if asked to draw a ray diagram) - 19What is refraction?The apparent bending of light when it moves from one substance (medium) to another
Towards normal when it enters a more dense substance (slows down)
Away from normal when it enters a less dense substance (speeds up) - 20What is diffraction?Spreading of waves when they pass an obstacle
- 21What is a sound wave?Pitch = Frequency
Volume = Amplitude - 22What is the electromagnetic spectrum?Spectrum of waves which can travel through a vacuum
Travel at the speed of light (300 million m/s) - 23What is the order of electromagnetic waves?Highest frequency + energy/Lowest wavelength: Gamma
X-Rays, U/V, Visible, I/R, Microwaves
Lowest frequency + energy / Highest wavelength: Radio - 24Which EM waves are used for communication?High wavelength & low energy (not damaging)
Light – e.g. morse code, optical fibres
I/R – e.g. optical fibres, TV remotes
Microwaves – e.g. Mobile phones
Radio – e.g. Terrestrial Radio (Radio 1 etc.) - 25Which EM waves are NOT used for communication?High energy waves
Have enough energy to be ionising
Can damage living tissue (eg. Mutate DNA) - 26What is the evidence that the universe is expanding?Redshift shows that galaxies are moving away from each other
The further away the galaxy the greater the redshift
The greater the redshift the faster the galaxy is moving away
Only true if the universe is expanding - 27What is the evidence that the universe started as a central point? (i.e. Big Bang)Redshift shows that galaxies are moving away from each other
The further away the galaxy the greater the redshift
The greater the redshift the faster the galaxy is moving away
Implies single point of origin - 28What is cosmic microwave background radiation?Leftover electromagnetic radiation from the big bang
As the universe expanded the wavelength stretched from gamma to microwave
Can only be explained by the big bang theory - 29What is the future of the universe?Depending on the density of matter in the universe…
Low density: Expand forever (not enough gravitational force to attract everything back together)
Critical density: Just enough to eventually reach a fixed size
High density: Universe will eventually contract back to a single point due to the force of gravity
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- Flashcards on P1 Part 2, created by ryan wigham on 03/05/2016.
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- ryan wigham
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