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OFFICIAL AQA GCSE PHYSICS 23rd May 2013 MARK SCHEME

Poll

How did you find it?

Hopefully the exam went well for you all. Please post to add to the mark
scheme.
QUESTIONS:
1) Diagram of eye (2 marks)
1b) Complete table (3 marks)
1c) Near point. What can you conclude from the data (2 marks)
1d) Suggest how data obtained could be improved (1 marks)
1e) Focal length = 40cm calculate power of lens (2 marks)

2) Compare stability of two rafts (2 marks)
2b) Complete ray diagram (4 marks)
2c) Two words to describe nature of image produced by the lens in the camera (2 marks)

3*) Describe the features of ultrasound and x-rays, and what happens when each type of wave entres the human body (6 marks)
3b) Explain why its not safe to use x-rays to produce image of an unborn child (2 marks)
3c) Give one use of ultrasound for medical treatment (1 marks)

4a) What property of liquid enables a hydraulic brake system to work? (1 marks)
4b) Calculate force exerted on the liquid by the master piston? (2 marks)
4c) How does the size of this force compare to force f made by the master piston?...
Give a reason for your answer... (2 marks)

5) G-Machine question.
Name of force...
Direction of force... (2 marks)
5b) State 3 conclusions that can be made from the graph (3 marks)
The speed of G-machine 1 is increased form 20m/s to 40m/s
Change in force? (1 marks)
5c) Explain why side A experiences a force (2 marks)
Draw arrows of the force acting on A and C (1 marks)
When horizontal, side b experiences no force...why? (1 marks)
5d) What can the operators do to make the G-machine rotate faster? (1 marks)
5e) Do you think we should spend money on space exploration? Yes or No? (1 marks)

6) Calculate the upwards force the man applies to the handle of his bag? (2 marks)
6b) When the man lets go of the bag handle, the bag falls and hits the floor. Why? (2 marks)
6c) Pendulum makes 10 complete swings every 160 seconds. Frequency + Unit) (3 marks)

7a) The alternating current flowing through the primary coil of the transformer creates an alternating current in the secondary coil? Why? (3 marks)
7b) Potential difference the charger supplies to the laptop? (2 marks)
Calculate the current in the primary coil? (2 marks)
7c) Give one other advantage of the switch mode transformer? (1 marks)
7d) Suggest one advantage of developing these batteries?

ANSWERS:

Q1- a) cornea and retina,
b) (i)Pupil/iris
(ii) ciliary muscle changes shape of lens,
(iii)lens changes shape to focus light from various distances.
(5 marks)

Q2- a)
b)
c) 2.5 D
(5 marks)

Q3- a) 6 mark x-rays
b) why x-rays are unsafe on fetus
c) use of ultrasound (kidney stones) .
(9 marks)

Q4- a) hydraulic pressure in liquid, work out pressure, is force bigger.
(5 marks)

Q5) a) space question- where the astronaut travels and the force, 3 conclusions, graph quesion, how motor works in thing, how it moves (arrows), is space exploration worth it, something else. 12 marks

Q6- a) Boat A had lower centre of mass and wider base(
b) why suitcase is stable
c) 1 Oscillation every 16 seconds
Formula was frequency=1/time period
so 1/16= 0.0625
(7 marks)

Q7 a) ray diagram (4),
b) Real, inverted and diminished (2)
(6 marks)

Q8) a) how transformer works (3), voltage is 20, amps is 0.3, advantage of switch mode, advantage of battery,.
(9 marks)

Sorry, if I take long to put up answers, got Exam tomorrow morning! I'll be getting them to you ASAP

(edited 10 years ago)

Scroll to see replies

1a:

Cornea
Retina.

The two calculations for 6
20 N
and then
69/230 = 0.3 amps

(edited 10 years ago)

Reply 3

Whooh1

Hydraulics
liquids are virtually incompressible

3
b- xrays are ionising so they can cause deformities in unborn child
c- kidney stone removal

pendulum calculation
T=1/f so I did 16/160=0.0625.

(edited 10 years ago)

Reply 4

rihannagirl

^ 3c was not prenatal scanning. it was removal of kidney stones/ other medical app.

Reply 5

Whooh1

Oh i thought it was either because it just said a Medical application?

Reply 6

ABC_12

Original post by Whooh1

Hydraulics
liquids are virtually incompressible

3
b- xrays are ionising so they can cause deformities in unborn child
c- prenatal scanning

i thought the question was "apart from scanning, name one other medical use"

so shattering kidney stones

Reply 7

Whooh1

I didnt read it properly then, never mind only 1 mark i only need a C to get a A

Reply 8

Heskey123

Original post by Whooh1

Hydraulics
liquids are virtually incompressible

3
b- xrays are ionising so they can cause deformities in unborn child
c- kidney stone removal

pendulum calculation
T=1/f so I did 16/160=0.0625. And then i think you had to do 1/0.0625 to get 16 hertz.

I thought that 1/0.0625 gives the period... the frequency is just 0.0625 i think.

Reply 9

Whooh1

Same i copied it from other thread, i wrote 0.0625

Reply 10

SpiggyTopes

It's clearly not an 'official' mark scheme!

Reply 11

ABC_12

moment calculation

a) Moment = Force x Distance
so Force = 36Nm/0.6m = 60 N

b) Would fall over because line of action was outside of base so there was a resultant moment

c)Took 160 sec for 10 swings
so 1 swing took 16 seconds

frequency = 1/ time period
so frqunesncy = 1/16 = 0.0625 Hz

Reply 12

rihannagirl

Original post by Whooh1

Hydraulics
liquids are virtually incompressible

3
b- xrays are ionising so they can cause deformities in unborn child
c- kidney stone removal

pendulum calculation
T=1/f so I did 16/160=0.0625.

cheeky thing editing it after my comment

Reply 13

rihannagirl

Original post by Whooh1

I didnt read it properly then, never mind only 1 mark i only need a C to get a A

calm down

Reply 14

LemonRice

For the one about the raft I said that the raft that was 'flatter' would be more stable as it had:
1) A lower Centre of Mass
2) A wider base

What did everybody else put?

Reply 15

ABC_12

Original post by LemonRice

For the one about the raft I said that the raft that was 'flatter' would be more stable as it had:
1) A lower Centre of Mass
2) A wider base

What did everybody else put?

same though i added that the riders could kneel so their centre of mass was lowered too and they are less likely to topple over

Reply 16

tohaaaa

Original post by LemonRice

For the one about the raft I said that the raft that was 'flatter' would be more stable as it had:
1) A lower Centre of Mass
2) A wider base

What did everybody else put?

SAAAAAAAAAAAAAAAAMEEEEEEEEEEE!!!!!

:banana:

What did everyone put for the last two?

For first I put about using less power even when turned on and no load is applied.

Second I put it would mean people wouldn't need to buy batteries all the time....