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

Original post by Fifi93

Here you go.

Thanks mate!! cheers :smile:

Good luck everyone!

Reply 261

Original post by Rogercbinboy

Post 128 on page 7 of this thread.

Bricking it myself atm.

Thanks!! Better stick to them now :biggrin:

You guys are legend!

Reply 262

anyone did the specimen paper no.11 b ii) ? I can't get the energy one at all. why it times by 3600 x 8?? per day.. isnt it 60x60x24 then?

Reply 263

Jke

Original post by wki

anyone did the specimen paper no.11 b ii) ? I can't get the energy one at all. why it times by 3600 x 8?? per day.. isnt it 60x60x24 then?

I got (1.8^-13)*0.8*(2*10^4)=2.88*10^-9
(2.88*10^-9)/75=(3.84*10^-11)=Absorbed dose per second
Absorbed dose*1=Effective dose per second
(3.84*10^-11)*60*60*24=3.31776*10^-6

(3.31776*10^-6)<(4*10^-6)

So it is below the safe limit. Hope that helps :biggrin:

Reply 264

Original post by Jke

I got (1.8^-13)*0.8*(2*10^4)=2.88*10^-9
(2.88*10^-9)/75=(3.84*10^-11)=Absorbed dose per second
Absorbed dose*1=Effective dose per second
(3.84*10^-11)*60*60*24=3.31776*10^-6

(3.31776*10^-6)<(4*10^-6)

So it is below the safe limit. Hope that helps :biggrin:

This makes much sense~ Thank you very much :smile:

Reply 265

41jms

1

whats the right hand rule guys?!

Reply 266

Original post by 41jms

whats the right hand rule guys?!

It tells you the direction of the current or the magnetic field, but it depends on what you're looking for.

Reply 267

Jke

Right hand rule is used for generators, when the motion creates a current/emf. Rather than the current causing motion.

Thumb = motion
first finger = field
second finger = current

Reply 268

Original post by Jke

I got (1.8^-13)*0.8*(2*10^4)=2.88*10^-9
(2.88*10^-9)/75=(3.84*10^-11)=Absorbed dose per second
Absorbed dose*1=Effective dose per second
(3.84*10^-11)*60*60*24=3.31776*10^-6

(3.31776*10^-6)<(4*10^-6)

So it is below the safe limit. Hope that helps :biggrin:

I did the same but apparently this answer is wrong. Apparently it's 3.84x10^-11x60x60x8

Reply 269

Rogercbinboy

11

Original post by Jke

Right hand rule is used for generators, when the motion creates a current/emf. Rather than the current causing motion.

Thumb = motion
first finger = field
second finger = current

That's the left hand rule - right hand rule is your right hand doing a thumbs up and the direction of the thumb is the direction of current in a wire and the way the fingers turn around your hand (clockwise if thumb is pointing away from you, anticlockwise if pointing towards you) is the direction of the magnetic flux loops that exist around a wire carrying a current.

Reply 270

Original post by Rogercbinboy

That's the left hand rule - right hand rule is your right hand doing a thumbs up and the direction of the thumb is the direction of current in a wire and the way the fingers turn around your hand (clockwise if thumb is pointing away from you, anticlockwise if pointing towards you) is the direction of the magnetic flux loops that exist around a wire carrying a current.

Exactly

It can also be the other way around.

Reply 271

Jke

Original post by Summerdays

I did the same but apparently this answer is wrong. Apparently it's 3.84x10^-11x60x60x8

Hmmm, maybe they assumed an 8 hour day at work? Thats all I can think of.

Reply 272

Original post by Summerdays

I did the same but apparently this answer is wrong. Apparently it's 3.84x10^-11x60x60x8

why is it 8 hours? it makes no sense :s-smilie:

Reply 273

readyforresults

Original post by wki

why is it 8 hours? it makes no sense :s-smilie:

Its typical ocr b to expect you to assume they'll be working "9 till 5"

Reply 274

a93

can someone pleeease help me with 9)d)i) from last years june paper
http://www.johnbright.conwy.sch.uk/depts/science/Content/Past_Papers/Y13/Physics/G495Jun10.pdf

the answer is 4 but i really dont get how.

Reply 275

Harry-AA

9

I put of physics for so long because of further maths :/ Kind of regretting it now. I need a B in this exam to get my A overall, that shouldn't be too much of an ask right? I hate this course, it sucks.

Reply 276

Original post by wki

why is it 8 hours? it makes no sense :s-smilie:

Jke

Hmmm, maybe they assumed an 8 hour day at work? Thats all I can think of.

I know, it's really silly. There's NO WHERE in the paper where it is implied that 8 hours (instead of 24) should be used. What utter nonsense!

Reply 277