# General Thoughts: Physics (1 Viewer)

#### Randox

##### Member
If you talked about lenz's law but didnt relate to back emf would you get a mark for the second part?

#### minagee3

##### New Member
7-marker:

one paragraph on cause, effect, reason of semiconductors (p-type and n-type). Forgot to do this --> Briefly mention the impact on society.

one paragraph on cause, effect, reason of superconductors (ceramics and metals (meissner)). Briefly mentioned the impact on society.

one paragraph on the overall impact on society from these technologies and assessment of cause and effect for both super/semi-conductors.

All one page.

Somewhere between 4 marks and 7 marks I'm guessing. Confident with 6 or 7.

Anyone want to clarify a mark?
but the question, specifically asked about the manipulation of materials to increase its conductivity. I only talked about semiconductors because of the whole process of doping. Superconductors aren't really manipulated, unless you think cooling them down is a way of manipulation. Like for example mercury under a certain temperature becomes a superconductors, without manipulation of the material. So yeah I think whether you included superconductors or not you should be fine.

#### someth1ng

##### Retired Nov '14
Mid 80s would be about 93.

#### Hypem

##### Member
For Q30 (b) (calculate rotational speed of the space station):

I equated everything correctly (mg = mv^2/r), with the m's cancelling out and g = 9.8 (and radius = 275 m).

I wrote 16.3 m/s. I just realised I put into my calculator v = sqrt(9.8*27) (missing the 5 at the end)

Do you still get 2/2, with the final working written down but the wrong number? Cause that's :/

#### JJ345

##### Member
For Q30 (b) (calculate rotational speed of the space station):

I equated everything correctly (mg = mv^2/r), with the m's cancelling out and g = 9.8 (and radius = 275 m).

I wrote 16.3 m/s. I just realised I put into my calculator v = sqrt(9.8*27) (missing the 5 at the end)

Do you still get 2/2, with the final working written down but the wrong number? Cause that's :/
Did you show the substitution correctly on the page, or plug it directly into your calculator without showing any other working?
If you did show correct sub. I guess there may be chance of 2/2 but if you didn't show correct substitution and just have the wrong answer then yeah 1/2.

#### Hypem

##### Member
Did you show the substitution correctly on the page, or plug it directly into your calculator without showing any other working?
If you did show correct sub. I guess there may be chance of 2/2 but if you didn't show correct substitution and just have the wrong answer then yeah 1/2.
Showed substitution. My calculator is dodgy sometimes and doesn't input stuff when I press the button :/ ... or I was rushing

#### anomalousdecay

##### Premium Member
Showed substitution. My calculator is dodgy sometimes and doesn't input stuff when I press the button :/ ... or I was rushing
Calculators aren't very dodgy. You just put it in wrong in the calculator.

#### anomalousdecay

##### Premium Member
but the question, specifically asked about the manipulation of materials to increase its conductivity. I only talked about semiconductors because of the whole process of doping. Superconductors aren't really manipulated, unless you think cooling them down is a way of manipulation. Like for example mercury under a certain temperature becomes a superconductors, without manipulation of the material. So yeah I think whether you included superconductors or not you should be fine.
It is a manipulation though......If not it would've said "manufacturing" like 2012 silicon age essay.

#### Menomaths

##### Exaı̸̸̸̸̸̸̸̸lted Member
please stop reviving thread, let it die away along with my sorrows

#### anomalousdecay

##### Premium Member
please stop reviving thread, let it die away along with my sorrows
You should be happy but. You got the photocell question.

#### joelferns27

##### New Member
fuah let me know if you do it
hope u do

#### Fizzy_Cyst

##### Well-Known Member
You should be happy but. You got the photocell question.
Talking to a person marking that particular question.. Seems they are taking Solar Cell..

Reasoning: "Over 50% of students would have gotten it incorrect."

Shit reason, but whatever..

Don't know if it is getting FULL marks though.

#### Menomaths

##### Exaı̸̸̸̸̸̸̸̸lted Member
Talking to a person marking that particular question.. Seems they are taking Solar Cell..

Reasoning: "Over 50% of students would have gotten it incorrect."

Shit reason, but whatever..

Don't know if it is getting FULL marks though.
That's lame...

~solved~

Last edited:

#### astroman

##### Well-Known Member
anyone have the answers to this paper?