OCR Gateway Physics P4P5P6 - 18/06/13

If anyone's staying up for a bit and want an extra tricky 12 mark question, I just made one (technically you're practicing for two different potential 6 markers in P6 by doing this!):

Laptops contain computer chips that are supplied by mains AC electricity. The electricity must be 'rectified' and 'smoothed' before reaching the computer chip so it is not damaged.

State which electrical components would be used to achieve this and explain how they work. (12 marks)

AC ---> Step Down Transformer ---> Less Rings on Secondary ---> Diode Bridge Circuit used to create DC electricity ---> Diodes reverse bias dictates a flow that always has output voltage ---> Capacitator used to smooth it out ---> charges when voltage is increasing, at maximum when voltage reaches peak ---> when voltage falls, capacitor discharges ---> keeps the ripple smaller ---> smooths out voltage

Correct

I'm screwed

Vin + (R2/(R1+R2))

Included?

Not in the specimen, so possibly not in the real exam


Posted from TSR Mobile

Good luck everyone


Posted from TSR Mobile

How did you all find it?
I thought it went quite well- there are a few questions that caught me out but overall, it wasn't too bad

What did you get on the question about parachutes? I got 56 for the first part but I wasn't too sure on the second part and got 24m


Posted from TSR Mobile

How did you all find it?
I thought it went quite well- there are a few questions that caught me out but overall, it wasn't too bad

What did you get on the question about parachutes? I got 56 for the first part but I wasn't too sure on the second part and got 24m


Posted from TSR Mobile

How did you all find it?
I thought it went quite well- there are a few questions that caught me out but overall, it wasn't too bad

What did you get on the question about parachutes? I got 56 for the first part but I wasn't too sure on the second part and got 24m


Posted from TSR Mobile

How did you all find it?
I thought it went quite well- there are a few questions that caught me out but overall, it wasn't too bad

What did you get on the question about parachutes? I got 56 for the first part but I wasn't too sure on the second part and got 24m


Posted from TSR Mobile

Wasn't it 56 to 4 m/s over 6 seconds?

I got something in the hundreds which I thought made sense?

I'm pretty sure it was something like this (180m):

http://www.wolframalpha.com/input/?i=56+m%2Fs+initial+velocity%2C+4+m%2Fs+final+velocity%2C+6+seconds