Mechanics 1 OCR - what equations / facts do I need to remember?

I was just wondering what important facts and equations I need to remember for the OCR mechanics 1 exam, if anyone knew them all I would be eternally greatful as they will be what I rmemeber for exam !

Reply 1

Unregistered

I am sitting the same exam I would also love to know this as i dont have a copy of the book they provide in the exam

Reply 2

Unregistered

if i remember right, learn all equations of motion
i.e.
v = u + at
v^2 = u^2 + 2as
s = ut + 1/2 at^2
s = (u+v)t/2

also learn resolving methods.

a useful one is tan x = coefficient of friction

component of weight down the slope is mgsin(x)
and normal contact force is mgcos(x)
i can't really remember much of M1 though :/

hope that helped.

Reply 3

mrmarsupial

tan x is coefficient of friction ?????? argh what ? lol

all the stuff u said after the equations of motion is the stuff I totally get lost on, I thought pure was pretty easy understood it all but prob made mistakes, D and D was a pistake easiest thing ever BUT MECHANICS ! I cant do it.

Reply 4

Zaphod

Originally posted by Unregistered
if i remember right, learn all equations of motion
i.e.
v = u + at
v^2 = u^2 + 2as
s = ut + 1/2 at^2
s = (u+v)t/2

also learn resolving methods.

a useful one is tan x = coefficient of friction

component of weight down the slope is mgsin(x)
and normal contact force is mgcos(x)
i can't really remember much of M1 though :/

hope that helped.

Well the top four I would agree with, but the others we definitely didn't do for M1 (OCR). There really aren't that many formulae you need to learn for M1, compared to P1 for instance. These are the ones I have noted down to learn:

F = u * N
(F=force, u=coefficient of friction, N=normal reaction)

a = dv/dt
v = integral(a dt)

v = ds/dt
s = integral(v dt)
(a=accel, s=displacement, t=time, v=velocity)

initial momentum = final momentum
ie. m1u1 + m2u2 = m1v1 + m2v2
(m=mass, u/v=velocity)

I'm pretty sure there are no formulae relevant to M1 in the formula book too, but I could be wrong.

k thanks

well i checked in my M1 book and it looks like you need to know how to resolve on an angled plane. i.e. mgcos(x) = normal contact force. which comes in very handy when finding frictional forces, etc...
but tan(x) = coefficient of friction, comes is useful when you need to know what angle the plane is at when given only the coefficient of friction or visa-versa. this is from M1 OCR book btw

Reply 7

Unregistered

tan(x) only equals the coefficient of friction where the velocity is constant if I remember right.

Reply 8

Unregistered

The important thing to remember when answering mechanics questions is:

1) Stay calm, the answer is within you somewhere
2) Draw a diagram with everything you know in it, write down all the equations you know. Look at everything you know, put it on the diagram. Do calculations even if you know they arnt what the question wants, they may inadvertantly lead you to the answer you need.
3) Look for relationships, READ THE QUESTION VERY CAREFULLY.
4) If you cant do it move on, DONT PANIC IT WILL EFFECT OTHER QUESTIONS LATER ON

Reply 9

mrmarsupial

I have just been trying to revise mechanics, I cant do it. Its all impossible it doesnt make sense Its so annoying I dont think I am gonna go to the exam, pure was so much easier mechanics is evil !