[Callum123]

First full correct UNOFFICIAL mark scheme for AQA Physics Unit 2 Higher - 30th Jan 2012


1
a)
i) Electrons transferred from pipe to beads causing beads to become negatively charged.
ii) 75cm^2 beads
iii) As the size increases the charge decreases.

b) Pipe is smaller and so less overall charge is transferred to the beads.

c)
i) Fine particles have a larger surface area.
ii) Earth pipes.
iii) These variables will affect the overall results.

2
a)
i) Nuclear fission is the separation of a heavier nucleus into lighter nuclei by 'firing' neutrons into the nucleus. This also releases more neutrons. Nuclear fusion is the fusing of lighter nuclei to form a heavier nucleus.
ii) Energy/heat

b)
i) Uranium 235
ii) Protons

3
a) Constant speed, accelerating, decelerating

b)
i) Braking Distance
ii) Speed

c)
i) 5000N in the opposite direction (to the left) - Newton's third law.
ii) Measure force exerted on specific points of the dummy.
iii) 4m/s^2

4
a)
i) 2V
ii) Straight line up to (0.8, 2), then a curve to (2, 12)
iii) As heat increases the filament in the lamp becomes more resistant.

b) 108J

5
a) They realised the pudding must contain a positive charge.

b)
i) Experiments didn't support the pudding model, and so it could not be correct.
ii) Not deflected, partially deflected, almost fully deflected by gold atoms.

c) Showed that the nuclear model was correct.

6
a) 98J
b) 9.6 kgm/s
ii) 9600N
iii) Force is equal to change in momentum (mass x velocity) over change in time. If change in time increases then overall force decreases.

[outsider95]

6a is wrong.

[dan673]

This is just a slightly more organized version of the first one. Are you really that desperate for recognition.. ? And as someone else suggested, some answers in this one seem dodgy.

[Callum123]

As far as I remember 6a) was a cricket ball with a mass of 0.16kg travelling at a velocity of 35m/s and so kinetic energy is 98J, and so sorry yes this is an error and you are correct.

The only other thread I have seen of this is someone who wanted a prediction for their grade and had a few mistakes, and so I made a full, correct version. Some of the answers on this may be brief and AQA will probably accept variations.

[ruks-96]

(Original post by outsider95)
6a is wrong.

yeh 6a was 98 J i think cos it was 1/2 x 0.16 x 35 ^2.

But thank you soo much for the mark scheme, really appreciate it

[Mr. T. Face]

(Original post by dan673)
This is just a slightly more organized version of the first one. Are you really that desperate for recognition.. ? And as someone else suggested, some answers in this one seem dodgy.

It seems right to me... Also surely there are better ways of getting recognition than posting a mark scheme. Are you really that desperate to degrade people for spending their time creating works which they distribute to the community for free, as well as to you. Please post constructive criticism in future, especially to those who have produced something with no recompense, rather than being disruptive and trollish. You disgust me.

Mr. T. Face.

[metaltron]

(Original post by Callum123)
First full correct UNOFFICIAL mark scheme for AQA Physics Unit 2 Higher - 30th Jan 2012


1
a)
i) Electrons transferred from pipe to beads causing beads to become negatively charged.
ii) 75cm^2 beads
iii) As the size increases the charge decreases.

b) Pipe is smaller and so less overall charge is transferred to the beads.

c)
i) Fine particles have a larger surface area.
ii) Earth pipes.
iii) These variables will affect the overall results.

2
a)
i) Nuclear fission is the separation of a heavier nucleus into lighter nuclei by 'firing' neutrons into the nucleus. This also releases more neutrons. Nuclear fusion is the fusing of lighter nuclei to form a heavier nucleus.
ii) Energy/heat

b)
i) Uranium 235/238
ii) Protons

3
a) Constant speed, accelerating, decelerating

b)
i) Braking Distance
ii) Speed

c)
i) 5000N in the opposite direction (to the left) - Newton's third law.
ii) Measure force exerted on specific points of the dummy.
iii) 4m/s^2

4
a)
i) 2V
ii) Straight line up to (0.8, 2), then a curve to (2, 12)
iii) As heat increases the filament in the lamp becomes more resistant.

b) 108J

5
a) They realised the pudding must contain a positive charge.

b)
i) Experiments didn't support the pudding model, and so it could not be correct.
ii) Not deflected, partially deflected, almost fully deflected by gold atoms.

c) Showed that the nuclear model was correct.

6
a) 98J
b) 9.6 kgm/s
ii) 9600N
iii) Force is equal to change in momentum (mass x velocity) over change in time. If change in time increases then overall force decreases.

I do not think this mark scheme is any more accurate than the last one. I have changed numerous answers where people have corrected me on mine. I have just removed neutrons from the correct answers and you still haven't changed the Uranium answer to Uranium- 235 as 238 would not be accepted. Your answer to the last question is debatable on whether it will get full marks. I'm sorry my mark scheme isn't up to your standards and feel free to use this one instead- just make sure this is correct.

[Callum123]

The last question would be accepted, and I was not aware that 238 would not be.

[Mr. T. Face]

I'm pretty sure that the question was "Why would a fielder move his hands backwards as he caught the ball?", I don't remember there being anything to do with "to reduce the force".

[metaltron]

(Original post by Mr. T. Face)
I'm pretty sure that the question was "Why would a fielder move his hands backwards as he caught the ball?", I don't remember there being anything to do with "to reduce the force".

Maybe can't remember now, the exam seems so long ago now! You're probably right, my memory has evaded me

[Callum123]

The last question was why would he move back, but to answer you had to use ideas of momentum. Hence F=Δmv/Δt. He would move back in order to reduce the force exerted on his hands.

[skaran]

For 1c ii I said use larger particles. Is that right?

[skaran]

For 5c, I said it proved results were valid and accurate. Is that right?

[Callum123]

(Original post by skaran)
For 1c ii I said use larger particles. Is that right?

Sadly this is incorrect, the answer was smaller particles. But this is only 1 mark so don't worry!

As for your other answer I am unsure as I do not remember the exact wording of the question.

[skaran]

Thanks

[metaltron]

(Original post by Callum123)
Sadly this is incorrect, the answer was smaller particles. But this is only 1 mark so don't worry!

As for your other answer I am unsure as I do not remember the exact wording of the question.

I don't know what you're on about Larger particles will have less charge so are less likely to cause an explosion. Surely in this fully correct mark scheme this answer could be considered

[Mr. T. Face]

The question was which particles are more likely to cause an explosion. Surely in this highly important Physics exam worth 25% of your GCSE, reading the question could be considered.

[Mr. T. Face]

(Original post by skaran)
For 5c, I said it proved results were valid and accurate. Is that right?

For 5c, the question was "Why was the fact that Rutherford's predictions matched the results so important?"

I think the direction that the examiners wanted you to go in was something to do with the scientific importance of the discovery of a new atomic model that went on to replace the plum pudding model, or at least that's what I tailored my answer to. I'm not sure if you would get the mark for what you put.

[skaran]

(Original post by Mr. T. Face)
For 5c, the question was "Why was the fact that Rutherford's predictions matched the results so important?"

I think the direction that the examiners wanted you to go in was something to do with the scientific importance of the discovery of a new atomic model that went on to replace the plum pudding model, or at least that's what I tailored my answer to. I'm not sure if you would get the mark for what you put.

Thanks

[skaran]

(Original post by Mr. T. Face)
The question was which particles are more likely to cause an explosion. Surely in this highly important Physics exam worth 25% of your GCSE, reading the question could be considered.

I thought 1c ii was how to reduce the chance of an explosion. I put use larger particles because they have less charge