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Physics Game Thread GCSE AQA 25th May 2016 Revision

Hi, Couldn't see a thread anywhere for this so just going to go ahead.

Rules:

- You must answer the question above you
- You must then ask another question

Rinse and Repeat

I'll start off with easy mode:

Name 2 properties of all electromagnetic waves

Reply 1

Crobby

Original post by redsoules

They travel at the same speed in a vacuum and are all transverse.
I think! Not sure :/ need to revise!

Ok, describe how a power station generates electricity!

Reply 2

TheConfusedMedic

Original post by Crobby

They travel at the same speed in a vacuum and are all transverse.
I think! Not sure :/ need to revise!

Ok, describe how a power station generates electricity!

haven't started revision so this will probably motivate me to start :colondollar:

- some sort of fuel is used to eventually heat water which evaporates and turns into steam (eg. coal is burned)
- steam turns turbine
- turbine powers generator
- generator generates electricity

? :biggrin:

EDIT: Describe what is meant by the Doppler effect.

(edited 7 years ago)

Reply 3

redsoules

Original post by surina16

haven't started revision so this will probably motivate me to start :colondollar:

EDIT: Describe what is meant by the Doppler effect.

Wavelength and Hz can change (increase in Hz and decrease in WL closer and Decrease in Hz and Increase in WL further away) Relative to the observers distance.

Reply 4

redsoules

Original post by Crobby

They travel at the same speed in a vacuum and are all transverse.
I think! Not sure :/ need to revise!

Ok, describe how a power station generates electricity!

Sorry, not all waves are transverse! Some are longitudinal. <--- It seems this is not the case? I found a source stating they are ALL transverse waves.

Explain how a convection current is formed in a fridge with freezer compartment.

(edited 7 years ago)

Reply 5

LNDNWASPS

The fridge has a higher KE than the freezer particles as a result the warmer particles in the fridge being less dense rise, the more dense particles in the freezer sink thus creating a convection current.

Reply 6

LNDNWASPS

Explain the two condritictory theorys on origin of the universe?

Reply 7

TheAverageTeen

The Big Bang: 14 billion years ago the universe expanded. it is still expanding. red shift is evidence of this
Steady state: The universe has always been like this

Name the 3 ways heat can transfer and explain each one

Reply 8

LNDNWASPS

Heat can transfer via conduction , convection and radiation
Conduction mainly happens in solid this is when the particles gain kinetic enegry and vibrate passing evn more KE onto the next particles
Convection mainly happens in liquids and gases - this happens when the particle gains kinetic energy, they become less dense as they expand, they rise, the more dense particles sink to the bottem thus creating a convection current
Raditaion emits heat out

Give two waves which are transverse and longitudinal?

Reply 9

redsoules

Original post by LNDNWASPS

Transverse - Uv/Ultraviolet and IR/Infrared Radiation

Longitudinal - Sound waves and P Waves [?] Earthquakes

What type of Reaction occurs in Nuclear power stations for the power to become usable?

Reply 10

georgiaesmehare

Original post by redsoules

Transverse - Uv/Ultraviolet and IR/Infrared Radiation

Longitudinal - Sound waves and P Waves [?] Earthquakes

What type of Reaction occurs in Nuclear power stations for the power to become usable?

Nuclear fission of nuclear fuels

What is red-shift and explain how it gives evidence for the Big Bang Theory

Reply 11

redsoules

Original post by georgiaesmehare

Nuclear fission of nuclear fuels

@georgiaesmehare I was looking for "chain reaction" :smile:

Nuclear Fission is correct though.

What is red-shift and explain how it gives evidence for the Big Bang Theory

When objects move away from us (or the observer), light is affected by the "doppler effect" (ie - Wavelength and Hz can change (increase in Hz and decrease in WL closer and Decrease in Hz and Increase in WL further away) Relative to the observers distance.)

The further away from us a star is, the more it's light is red-shifted. (Implying that distant galaxies are moving away from us and the further it is away, the faster it is moving.)

This gives us evidence that our universe is expanding. Suggesting everything is moving away from everything else.

I want to add that this MIGHT come up and I'm not even fully aware of the topic really. Spectrum absorption being one of them)

Describe and explain how Hydroelectric power stations function.