OCR Physics B G495 Field and Particle Pictures June 21st 2011 Exam Thread

Can anyone help me with relitivity and relitvistic calculations I can calculate the relitvistic factor but what do you do when you have to apply it to half lifes or other times?

It is simply, time x relitivistic factor = relitive time

Reply 301

41jms

1

are the article practice qs worth doing? i dont really understand any of it! should i just revise from the cgp guide instead?

Reply 302

Swindan

8

How good are pre-2008 past papers? I think that's the year the specification changed, but do those before then still bare a lot of resemblance?

Reply 303

Summerdays

10

Original post by Swindan

How good are pre-2008 past papers? I think that's the year the specification changed, but do those before then still bare a lot of resemblance?

They bare A LOT of resemblance. In fact the questions in those papers are as hard/ even harder than the 'stretch and challenge' questions :smile:

Reply 304

Geekchic17

Anyone doing those case study questions? ( http://www.school-portal.co.uk/GroupDownloadFile.asp?GroupId=642525&ResourceID=3903515 )

I'm stuck on question 1 .. It's probably really easy but yeah ..

probably doomed to fail this module..

Reply 305

Summerdays

10

Original post by Geekchic17

Anyone doing those case study questions? ( http://www.school-portal.co.uk/GroupDownloadFile.asp?GroupId=642525&ResourceID=3903515 )

I'm stuck on question 1 .. It's probably really easy but yeah ..

probably doomed to fail this module..

Which part?

Reply 306

Unkempt_One

13

Original post by bear54

Which way does current flow, positive to negative? I heard this is what scientists thought ages ago and they didn't bother to change it when it's actually negative to positive?

Current flows from positive to negative. Electrons flow from negative to positive.

Reply 307

Geekchic17

Original post by Summerdays

Which part?

part a) lol .. I just don't know where to take it at all :L

Reply 308

Summerdays

10

Original post by Geekchic17

part a) lol .. I just don't know where to take it at all :L

We know that the weight of the ball is proportional to time, and we are trying to porve if the distance is proportional to time^2, i.e.: you are proving if distance is proportional to weight^2

so you are using this equation Distance = k(mg)^2, and proving if k is constant by a certain amount of sig figs.

Reply 309

Rogercbinboy

11

Original post by 41jms

are the article practice qs worth doing? i dont really understand any of it! should i just revise from the cgp guide instead?

I'd recommend trying to read around the article and learn some formulae (like pendulums in simple harmonic motion, circular motion for the earth spinning, materials i.e. young's modulus = stress/strain) even if you can't do practise questions - since it's 40% of the course so without at least some knowledge even with the best grade in section A and B it wouldn't go above a D.

Also finding those questions hard though, basically all the uncertainties ones I can't do so hopefully there wont be too much of a focus on that.

Reply 310

Geekchic17

Original post by Summerdays

We know that the weight of the ball is proportional to time, and we are trying to porve if the distance is proportional to time^2, i.e.: you are proving if distance is proportional to weight^2

so you are using this equation Distance = k(mg)^2, and proving if k is constant by a certain amount of sig figs.

ah that'll be where i went wrong
i tried that, but instead of weight i just did mass,
ahh
im so stressed.

im so not going to uni cause of stupid physics :L
maybe cause of stupid me, either way ..

sucks to be me!

x

Reply 311

Summerdays

10

Original post by Geekchic17

ah that'll be where i went wrong
i tried that, but instead of weight i just did mass,
ahh
im so stressed.

im so not going to uni cause of stupid physics :L
maybe cause of stupid me, either way ..

sucks to be me!

x

Mass also works. In fact I original used mass instead of weight, and so does the MS :tongue:

OCR B is a terrible course.

(edited 12 years ago)

Reply 312

thatgu

1

Original post by thatgu

Can anyone help me with relitivity and relitvistic calculations I can calculate the relitvistic factor but what do you do when you have to apply it to half lifes or other times?

It is simply, time x relitivistic factor = relitive time

Sorry to be a pain but can someone help me with this and has there only been one other g495 paper,2010.

Reply 313

Jke

So how is everyone revising? Doing past papers? or CGP book mainly? Anyone have a collection of G495 questions? :smile:

Reply 314

Summerdays

10

Original post by Jke

So how is everyone revising? Doing past papers? or CGP book mainly? Anyone have a collection of G495 questions? :smile:

I barely use the CPG book... I don't think it explains the concepts deeply enough. But that's like, my opinion man :tongue:

Reply 315

41jms

1

Original post by Rogercbinboy

I'd recommend trying to read around the article and learn some formulae (like pendulums in simple harmonic motion, circular motion for the earth spinning, materials i.e. young's modulus = stress/strain) even if you can't do practise questions - since it's 40% of the course so without at least some knowledge even with the best grade in section A and B it wouldn't go above a D.

Also finding those questions hard though, basically all the uncertainties ones I can't do so hopefully there wont be too much of a focus on that.

i know your right arh thats making me really :frown:

now, i need to get an A in physics which i definitely wont at this rate :'( could you possibly list atleast some of these formulae that you are talking about, please? you can have all my pos rep!!

Reply 316

Summerdays

10

Original post by 41jms

i know your right arh thats making me really :frown:

now, i need to get an A in physics which i definitely wont at this rate :'( could you possibly list atleast some of these formulae that you are talking about, please? you can have all my pos rep!!