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transmission question (2 Viewers)

Kimyia

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What did everyone put for the tranmission question??? A, B or C!
 

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Re: General Thoughts: Physics

What did everyone put for the tranmission question??? A, B or C!
Best would be B because A was high current (max power lost) and C was way too fkin expensive :p
 

Kimyia

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Re: General Thoughts: Physics

Yay I put B :)
 

nerdasdasd

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Best would be B because A was high current (max power lost) and C was way too fkin expensive :p
Ah damn , but the power loss is b is way too much so c is correct.
 

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Re: General Thoughts: Physics

Ah damn , but the power loss is b is way too much so c is correct.
It asked you which design is the BEST, so B because it is relatively cheap and very less power lost :p
 

machine2035

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Re: General Thoughts: Physics

Ah damn , but the power loss is b is way too much so c is correct.
What did you get for powerloss. I only got something like 1.6MW. So they would have to generate 101.6MW at the power station. Compared the others, this was the lowest to reach 100MW at the substation.
 

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Re: General Thoughts: Physics

I had 1.6 MW for B, 3 MW for C (due to the cooling stations) and something much higher for A.
 

nerdasdasd

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The total cooling for c was 300k? It was 3kw per km?
 

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Re: General Thoughts: Physics

I had 1.6 MW for B, 3 MW for C (due to the cooling stations) and something much higher for A.
shouldnt you talk about losses percentage wise, because the first one was a higher output voltage..energy loss/total output power
 

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Re: General Thoughts: Physics

I had 1.6 MW for B, 3 MW for C (due to the cooling stations) and something much higher for A.
ah fuck man, I didn't do calculations, and I just explained it :p
 

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Re: General Thoughts: Physics

I started like that when I realised the question specifically mentioned calculations.. I went below "End of question" on the page so the marker probs be mad.
They will probs take away 1 mark :S
 

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Re: General Thoughts: Physics

^But you need to use more power for cooling in C than you would lose in B, right?
(My calculations were fucked so I'm not 100% sure on this)
 

brianphamm

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Re: General Thoughts: Physics

Really fair exam imo but 2 things...



It didn't ask about price, so C was actually the best choice because of its efficiency
and also for that length contraction one it was 40.2 cm because it was asking from the electron's point of reference. I came across a question very similar to this one where you had to really think about your reference points
But otherwise I pretty much agree with everything else :)
But C uses 3MW of power, which can be said to be 'losing', so in the end you'll only get 97MW. B on the other hand, loses only 1.6MW of power and gets 98.4MWin the end. Wouldn't B be the better choice?
 

Automatia

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Re: General Thoughts: Physics

Really fair exam imo but 2 things...



It didn't ask about price, so C was actually the best choice because of its efficiency
and also for that length contraction one it was 40.2 cm because it was asking from the electron's point of reference. I came across a question very similar to this one where you had to really think about your reference points
But otherwise I pretty much agree with everything else :)
That is not correct. C was not the most efficient because of the cooling which required more energy than b lost in resistance.
 

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Re: General Thoughts: Physics

^But you need to use more power for cooling in C than you would lose in B, right?
(My calculations were fucked so I'm not 100% sure on this)
Yep. A power station every 1 km for 100 km that utilises 3 kW at each station. Adds up to a total power loss of 3 MW, higher than the 1.6 MW power loss of solution B.

Edit: or answered five times already. Too easy. =P
 

LlamaBoi

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Re: General Thoughts: Physics

But C uses 3MW of power, which can be said to be 'losing', so in the end you'll only get 97MW. B on the other hand, loses only 1.6MW of power and gets 98.4MWin the end. Wouldn't B be the better choice?
It makes sense with your working but we must have calculated our efficiencies differently :/
I got around 6 MW for B and 3 MW for C so with my working its correct as well...wonder how theyll mark it
 

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