OCR M1 - 31st May 2012 :)

for that A and B and distance question, I subtracted 1 instead of adding 1, do you think this'll lose 1 or 2 marks?

also do you think it'll be possible to get full ums for 70-71/72?

I think this will lose you 1 if you laid it out as distance by A and distance by B and then looked at them together, but 2 if you did something strange. Hmm.... I'd have to wait for the general consensus to come out but I'm going to say that 71/72 will be 100.. so maybe

ah cool, I didn't really think much about that question, I just worked out the difference in the distance that A and B travelled, then (obviously wrongly) reasoned that since A has to cover 1m less, it's distance from B is 1m less?

I just need a high mark in this to balance out the atrocity that is D1..

I think you just equated the distance that A travelled and the distance that B travelled plus 1.... I really can't remember mate, but if you got the same answer as me, you should be okay

Could someone please walkthrough question 4? I don't remember getting 6.02 :/

Do you get error carried forwards? Primarily for the last question. Just say you got 7ii) wrong... (I put 3.11 + t)

nah i got 10.6 instead of 12.6, cause difference was 11.6 so I should have added 1 instead of taking 1...

New R (cos of force being removed)= 28N
F=mu R
mu=0.577
F=0.577 x 28
Newton II
0.577 x 28 = 28/9.8 x a
Rearrange to find a
s= 3.2 u=u v=0 a= -(0.577 x 9.8)
u= sqrt(2 x 3.2 x [0.577 x 9.8]) = 6.015765...

For Q1 ii), was force E 15N, i.e. same as resultant from previous question?

New R (cos of force being removed)= 28N
F=mu R
mu=0.577
F=0.577 x 28
Newton II
0.577 x 28 = 28/9.8 x a
Rearrange to find a
s= 3.2 u=u v=0 a= -(0.577 x 9.8)
u= sqrt(2 x 3.2 x [0.577 x 9.8]) = 6.015765...

61/72 that's the minimum I reckon I got and the maximum is 66/72, any idea what type of UMS I am looking at?

Yes it is the same as the resultant, but the resultant is 17N, not 15N.

OK, as long as it's the same as the resultant and angle is 180- the angle in i). Can you remember the two component forces, maybe I got 17 but can't remember.

I'm hoping 60 is around 85ums lol