EDEXCEL A2 Physics EXAM Unit 4 Physics On The Move 20th June 2016 (NOT I-A-L)

Resolve vertically: F*sin22 = 80 * 9.81 gives F = 846

Set horizontal component equal to mv^2/r, rearrange to get

r = (80 * 9^2) / (846 * cos22) which gives you 20.4m

you got your sin and cosine mixed up, but everything else is right.

Reply 161

Maetras

9

It's not gonna be 70+ for A*, right? 66?

Reply 162

Z1228

2

I got 0.14m for the radius??? Which I thought was right because cycles can't tilt like 20m

Reply 163

oShahpo

20

Original post by Z1228

I got 0.14m for the radius??? Which I thought was right because cycles can't tilt like 20m

It's the radius of the bend, i.e. the radius of the circle the bike covers.

Reply 164

bertolli1

has anyone seen an unofficial mark scheme?

Reply 165

guidoblee

I think the paper was pretty good overall, as normal with physics doing further mechanics modules in maths always helps. Any other ideas on why the H+ ion left no track after the photon interaction? I said it was because it wasn't moving, something about momentum

Reply 166

oShahpo

20

Original post by guidoblee

I think the paper was pretty good overall, as normal with physics doing further mechanics modules in maths always helps. Any other ideas on why the H+ ion left no track after the photon interaction? I said it was because it wasn't moving, something about momentum

Same. What did you put for the bit about the spokes and the speedometer?

Reply 167

guidoblee

Original post by oShahpo

Same. What did you put for the bit about the spokes and the speedometer?

The speedo will overestimate the speed - decrease in radius means the bike travels less far for the same rotation.

Reply 168

oShahpo

20

Original post by guidoblee

The speedo will overestimate the speed - decrease in radius means the bike travels less far for the same rotation.

Yea I said the same thing, but I also that the value itself wouldn't change as the angular velocity stays the same, does that negate the first bit I said?

Reply 169

PhysicsIP2016

2

Original post by jtebbbs

I put the velocity was greater for the high speed electron, and r=mv/BQ so its path would have a greater radius i.e. it would be less deflected

Struggled with the friction one, I put so that no momentum was transferred to the track and the system remained 'closed'...? Also struggled with that 5 marker with light gates and gliders, what did other people get for that?

For the flat tire, the radius would decrease, and the speed on the speedo is inversely proportional to radius so the speedo would display a higher speed than the true value

Surely the speed is directly proportional? v=2pir/T?

Reply 170

PhysicsIP2016

2

Original post by target21859

What did people put for why it wasn't deflected as much, effect of flat tire, need for low friction and graph question? Grade boundaries?

For the low friction one I put that there would be no external forces acting on the gliders (the COM states that momentum is conserved provided there are no external forces).

Reply 171

kidlikethat

1

Original post by guidoblee

I think the paper was pretty good overall, as normal with physics doing further mechanics modules in maths always helps. Any other ideas on why the H+ ion left no track after the photon interaction? I said it was because it wasn't moving, something about momentum

Yeah I said there was no track because the H+ was stationary too!

Reply 172

kidlikethat

1

anyone else notice how little maths was in it? Pretty much all qualitative!

What did people get for q10? The kinetic energy and momentum multiple choice?

Reply 173

oShahpo

20

Original post by kidlikethat

anyone else notice how little maths was in it? Pretty much all qualitative!

What did people get for q10? The kinetic energy and momentum multiple choice?

1/root6

Reply 174

ColeNate

7

Original post by kidlikethat

anyone else notice how little maths was in it? Pretty much all qualitative!

What did people get for q10? The kinetic energy and momentum multiple choice?