ShutUpLegs
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Everyone just post all the questions you can remember and we'll try to group them and order them later.

Question 1
Which part of the atom has no charge? The neutron.
Which part of the atom has the greatest specific charge? The electron.
Which part of the atom when removed leaves a different isotope of the element? The neutron.

When it undergoes beta decay it produces an electron and another particle. Name this particle? Anti-(electron)neutrino.
What happens to the proton number and atomic mass of Technetium when it undergoes beta- decay? The proton number increases by one and atomic number remains the same.

Calculate the specific charge of the Technetium nucleus (43 protons and 99 nucleons if I remember) and list a suitable unit? 4.161374221\times10^7 so rounded gives 4.2\times10^7 or 4.16\times10^7 Ckg-1.

What is the gauge boson for the electromagnetic force? (Virtual) photon.
What is the gauge boson for the weak force? W (and Z) bosons.

Question 2
What's the name of the process where a gamma ray decays to form a particle and antiparticle pair? Pair production.

Calculate the photon's energy?

What happens to the excess energy? It's changed to kinetic energy of the positron and electron.

What happens to the emitted positron? The positron would soon come into contact with its anti-particle the electron and annihilate producing two (high energy gamma) photons. 2 marks

Draw the feynman diagram for electron capture?

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What's meant by the term ohmic conductor? A conductor whose voltage is directly proportional to the current flowing (when temperature's constant).

What is meant by the term superconductor? A conductor which has zero resistance at or below a certain temperature (so no energy is wasted).

List a use for a superconductor? Power cables which transfer energy without waste. High power electro-magnets. (add more)

Question 5
Draw a circuit diagram to show how the component can be tested? 2 marks.

How could said circuit diagram be used to test whether or not a component is ohmic? 6 marks.

Question 6
What is the total resistance of the circuit? 11KΩ.

What is the current that flows in the circuit? 1.1mA

Complete the table with the correct PDs filled in?
A-C: 6V
D-F: 4V
C-D: 2V

What will happen to the voltmeter readings when the resistance of the thermistor decreases;
Between points A-C? The voltmeter readings will remain the same as the voltage supplied and value of the resistors will be unchanged. 2 marks.
Between points D-F? 2 marks.

Question 7
Calculate the resistance of a wire measuring 0.75m in length, with a cross-sectional area of something and the resistivity of copper is something.
A lamp of power rating 25W running at 12V is connected to a power supply of negligible internal resistance using two of those wires.
Calculate the current in the circuit when the lamp is running at its rated power?
Calculate the pd across the lamp?
Calculate the emf of the power supply?
When the lamp is connected to a power supply with some internal resistance, explain what happens to it?

Correct anything that you think we will compile a final version with the right order and all corrections.
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AboveTheLine
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Question 5

Jimbob the mechanic wants to find out of this dodgy component he has is ohmic or not. Draw a circuit diagram worth 2 marks and describe how he would go about testing. Your answer should include details of measurements taken, something else, and how to observe whether it's ohmic or not.

Diagram was straight forward,
The possible points to include are in the exam discussion thread somewhere.

Question 6

What is the total resistance of the circuit?
Voltage table at points:
A-C: 6V
D-F: 4V
C-D: 2V

What will happen to the voltmeter readings when the resistance of the thermistor decreases…
Between points A-C
Between points D-F

Question 7
Calculate the resistance of a wire measuring 0.75m in length, with a cross-sectional area of something and the resistivity of copper is something.
A lamp of power rating 25W running at 12V is connected to a power supply of negligible internal resistance using two of those wires.
Calculate the current in the circuit when the lamp is running at its rated power.
Calculate the pd across the lamp. I think?
Calculate the emf of the power supply
When the lamp is connected to a power supply with some internal resistance, explain what happens to it.
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pkiller162
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Answer-

What happenes to the exess energy?
It gets added to the electrons + positrons kinetic energy


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FLLF
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Q6 resistance is 11k ohm and current of circuit is 1.1mA
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ShutUpLegs
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Can anyone remember what order the energy level and superconductor question came up in? And also, what was the point D-F? I can't remember if it was the thermistor or 10 kohm one.
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AboveTheLine
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(Original post by SamHedges)
Can anyone remember what order the energy level and superconductor question came up in? And also, what was the point D-F? I can't remember if it was the thermistor or 10 kohm one.
I replicated the potential divider question diagram, so I can tell you that point D-F was the voltage across the thermistor. Point B-D was across the 10Kohm.
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FLLF
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(Original post by SamHedges)
Can anyone remember what order the energy level and superconductor question came up in? And also, what was the point D-F? I can't remember if it was the thermistor or 10 kohm one.
Superconductor question was in the same one as the six marker, I believe question5
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Parente
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The definition of the ohmic conductor came before the circuit diagram and the six marker (just before you had to draw the circuit diagram). There was a question like, 'What is the critical temperature?' for the superconductor bit too.
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FLLF
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If you need specific answers: q7) r=0.98, I=2.1, v=2.0, emf=16

Internal resistance would cause the lamps brightness to decrease. This is because internal resistance limits the current, and therefore reduces the voltage across the lamp. As a consequence, the lamp has a lower power (p=iv)
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ShutUpLegs
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What were questions three and four?
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resist
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The excitation/ionisation questions I think. I seem to remember some wave-particle duality questions too. Can't remember specifics though, sorry.
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Dr.Rivka
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Q why are photons of different frequencies emiited?
Q state and explain how photons of different frequencies emiited?
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yasir.mir
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Question 4, about superconductors, also had a question that went something like 'State what is meant by critical temperature'
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Jimmy20002012
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(Original post by SamHedges)
What were questions three and four?
Wasn't the question about calculating the photons frequency not the photons energy?


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ridleyDante
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This thread didn't get finished then...
Would have been helpful.

Thanks for the ones that were.
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Celineman
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why V=2.0??
(Original post by FLLF)
If you need specific answers: q7) r=0.98, I=2.1, v=2.0, emf=16

Internal resistance would cause the lamps brightness to decrease. This is because internal resistance limits the current, and therefore reduces the voltage across the lamp. As a consequence, the lamp has a lower power (p=iv)
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