OCR Physics A G484 - The Newtonian World - 11th June 2015

Original post by Username13

I thought it was 90% UMS for the A2 exams and 80% average UMS for the A2 practical and AS exams/practical to get an A*?

no

Original post by Makashima

Wait what. There's A* boundaries for A2 practicals too ???

38 raw = a star on the practical.

Original post by morgan8002

OCR don't publish theirs, but it's around 37 or 38 for an A*(varies year on year).

This yeah

Reply 202

Damien_Dalgaard

Original post by morgan8002

Lucky! I'll probably find mine out next week but at the most it'll be around 33-34. I really need an A* overall.

are you applying to Oxbridge?

tbh exams really matter get 150 on g485 then only 120 from the other two components.

Reply 203

username1560589

20

Original post by Damien_Dalgaard

are you applying to Oxbridge?

tbh exams really matter get 150 on g485 then only 120 from the other two components.

No, I got rejected.

I think G484 is easier(more maths), so will probably get a higher mark in that. I will try to get 100% in both exams though.

Reply 204

Damien_Dalgaard

Original post by morgan8002

No, I got rejected.I think G484 is easier(more maths), so will probably get a higher mark in that. I will try to get 100% in both exams though.

sorry.

Maybe last years paper was tough for g484.

Will you post a levels apply?

Reply 205

lollipopsftw

Guys ive attached a graph for g484 and g485 showing the grade boundary trend. Whats your opinion?

a star g484.png10.8KB

a star g485.png10.0KB

Reply 207

Wow thats really nice of you for those data...
So for G484, the maximum marks you can afford to lose for an A would be 12 marks
And for G484, the maximum marks you can afford to lose for an A would be 19 marks

Oh well, Im aiming for a B so maybe for me its like 15 marks ?

Reply 208

lollipopsftw

Original post by Makashima

Wow thats really nice of you for those data...
So for G484, the maximum marks you can afford to lose for an A would be 12 marks
And for G484, the maximum marks you can afford to lose for an A would be 19 marks

Oh well, Im aiming for a B so maybe for me its like 15 marks ?

That's alright :smile:

shall I make a graph for a B?

Reply 209

Original post by lollipopsftw

That's alright :smile:

shall I make a graph for a B?

Omg yes please, if it is not a hassle ^_~

Reply 210

lollipopsftw

Original post by Makashima

Omg yes please, if it is not a hassle ^_~

Original post by lollipopsftw

x

Thank you very much! ^_~

Reply 212

Edit:

Ok time period is independent from amplitude thus in damping, the time period is constant but simply the changing bit is the velocity in order to have the same time period
So velocity increases or decreases?

Is this right? Iduunooo

(edited 9 years ago)

Reply 213

BrokenS0ulz

3

Original post by Makashima

Edit:

Ok time period is independent from amplitude thus in damping, the time period is constant but simply the changing bit is the velocity in order to have the same time period
So velocity increases or decreases?

Is this right? Iduunooo

I think it would mean velocity decreases, look at v=2pif x X, damping reduces the displacement, and so will reduce the velocity

Reply 214

Hilton184

9

Original post by Makashima

Edit:

Ok time period is independent from amplitude thus in damping, the time period is constant but simply the changing bit is the velocity in order to have the same time period
So velocity increases or decreases?

Is this right? Iduunooo

When you damp something, the thing is not strictly in simple harmonic motion. You do not have the same time period when you damp something. In fact the point of critical damping is to complete stop oscillations occurring.
In order to keep the time period the same you would have to increase the velocity because you are decreasing the amplitude. However the velocity doesn't increase - how could it, you are removing evergy from the system in damping.

Posted from TSR Mobile

(edited 9 years ago)

Reply 215

gothmog827

Examples of resonance? Thanks

Posted from TSR Mobile

Reply 216

L'Evil Fish

OP

18

Original post by gothmog827

Examples of resonance? Thanks

Posted from TSR Mobile

Urmmm

Washing machine casing??
Microwaves, send in radiowaves to increase amplitude of oscillation of water molecules in food to heat it up?

Reply 217

Hopstano

Original post by L'Evil Fish

Urmmm

Washing machine casing??
Microwaves, send in radiowaves to increase amplitude of oscillation of water molecules in food to heat it up?

Natural frequency of the water molecules match the driving frequency of the microwaves hence they oscillate with maximum amplitude?

Reply 218

L'Evil Fish

OP

18

Original post by Hopstano

Natural frequency of the water molecules match the driving frequency of the microwaves hence they oscillate with maximum amplitude?

Yeah and further increase

Reply 219