OCR M1 (not MEI) Official Thread 24/01/2011

Well you can't get better than an A really can you?! (I know you mean UMS).

It could be argued that this question assumes knowledge beyond M1 as this is more commonly tested in M2.

indeed, this was a resit to try and get an A overall, i needed 93% in it to get that, and was getting over this on practice tests. but loosing 5 marks on that question means that i have to have made no silly mistakes in the rest of the exam even though i got all the same answers as you.

ah, that explains it, i was always thinking to keep vertical horizontal forces seperate...
granted i know that's silly, but still, what was done...

Original post by yellowlight

I didn't think it meant the exact instant the object stops, but just when it is at rest in general. Wouldn't the friction then act upwards to prevent the force of gravity from moving it down the slope?

Ah I didn't read the question properly. I assumed the object was instanteously at rest before coming back down the slope (in which case we could treat the friction as being zero for that instant as it switches direction). In this case the friction would certainly act up the slope to hold the object in position.

Sorry about that, I will amend the answers. Check again in a minute to see if you were right with your figures.

Edit: You were.

(edited 13 years ago)

Original post by Lazarusasaur

indeed, this was a resit to try and get an A overall, i needed 93% in it to get that, and was getting over this on practice tests. but loosing 5 marks on that question means that i have to have made no silly mistakes in the rest of the exam even though i got all the same answers as you.

ah, that explains it, i was always thinking to keep vertical horizontal forces seperate...
granted i know that's silly, but still, what was done...

In M2 there are quite often ladders touching walls and you get a normal contact force sticking out of the wall and a frictional force that stops the ladder sliding down the wall and they ask you to work out the angle and magnitude of the resultant contact force.

Reply 103

purplestarfish

Original post by Mr M

In M2 there are quite often ladders touching walls and you get a normal contact force sticking out of the wall and a frictional force that stops the ladder sliding down the wall and they ask you to work out the angle and magnitude of the resultant contact force.

Mr M, was this in your opinion, a paper of average difficulty?

Reply 104

Dunney101

crap for question 6 part three, i got t=5 and put it into the equation x=1/3t^3 - 9t^2+46/3 so ended up getting -168m, how many marks do you think i will lose for squaring t in the equation on part 3? thanks

Original post by purplestarfish

Mr M, was this in your opinion, a paper of average difficulty?

No it was slightly more difficult than average.

Reply 106

YGB Jammy

1

Thought this paper was pretty horrid tbh, although I think I've got a high B around 76% I think. Better than my last grade so hopefully this will pull my final grade up a bit as last time my 1 B pulled my overall AS down to a B despite getting 2 As! Grr.