Struggling with revising for Physics

Thanks, in short, things on Motion, Forces and Energy.
I'm ok with the theory aspects but when it comes to calculations and figuring out what to do using principles etc, I kind of go blank a bit.

Ok I'm not very good at explaining but I'll try my best.
(a) You are told that the original length of the spring is 2cm. So the extension must be 6cm or 0.06m. Use the formula F=kx and rearrange to make k the subject. k=3/0.06= 50.

(b)(i) For this part you want to work out the potential energy when the spring is in equilibrium and the potential energy when the spring isn't in equilibrium (i.e. use fig 7.2). Use E=0.5kx^2. Fig 7.1 E= 0.5 x 50 x 0.06^2 = 0.09 J. Fig 7.2 E= 0.5 x 50 x 0.1^2= 0.25 J. The difference between the two is 0.25-0.09=0.16 J and that's your answer.

(ii). This one is weird. For the spring to be in equilibrium in fig 7.1 there must be a force of 3N acting in the upwards direction (opposite weight) so that the resultant force is 0N, yes? The spring in fig 7.2 is NO LONGER IN EQUILIBRIUM. There's still a force acting in the opposite direction to weight, but it no longer is equal to weight. Use F=kx to work out what it is F= 50 x 0.1 = 5N. The upwards force is 5N, weight is 3N so the resultant force is 5-3=2N (take them away since they act in opposite directions). You can now use F=ma to work out what the acceleration is. Mass= 3/9.8 (from W=mg) a= F/m => 2/(3/9.1) which comes to 6.5 ms^-2.

Let me know if this doesn't make sense!

Are you using the formula booklet? Just writing down the formulas you see in the booklet that you think may be related to the question might trigger something

Vector
Scalar
Displacement
Instantaneous Speed
Average Speed
Velocity
Acceleration
Newton
Terminal Velocity
Centre of Gravity
Torque of Couple
Moment
Thinking, braking and stopping distance
Work Done
Joule
Watt
Conservation of Energy Principle
Power
Stress
Strain
Young's Modulus
Elastic Deformation
Plastic Deformation
Elastic Limit
Ultimate Tensile Strength

I think that's all.

Thanks, I need to remind myself of Elastic and Plastic deformation.

http://www.mediafire.com/view/frs1nme7xoe3zzm/G481-01_Jun14.pdf

Here's the link. I was lucky to have someone kindly post it here.

Do you by any chance have the mark scheme?

Yea, a guy sent a link of all the papers from last year:

https://www.mediafire.com/folder/p2jf5nrw7p2cqb7,frs1nme7xoe3zzm,2ln99twglulpjl7,8o9qezz21372d6v/shared

I don't know why but I could never feel confident with studying for Physics. Thank God for M1 in maths as it really helped with certain concepts but my first exam is on the 19th May and I still need to learn Chapter 4 to 8 for Mechanics. I don't know the best way to prepare for mechanics. I only have a week and it seems that I am only getting marks in the definitions and simple areas. I'm barely scrapping an E.
At this rate, it's getting frustrating. I'm using the textbook to study even, maybe that's the problem- as I need the theory first I thought book first, past papers later but once I try the past papers, I get confused.

What did you guys get on controlled assessment?

I got 10/10, 17/20 and 8/10 (35/40)

Hopefully an A is still 34+/-

Are you doing AQA?

I flopped mine and got 29 in total
I need to get 80-90 in G482 to hopefuly secure an A while right now i get about 55-60 out of 100
While in G481 i get about 46-50 marks

Posted from TSR Mobile

Mate that G481 june 2014 paper is deadly... Ive struggled with it, whilst the other papers are not so bad... Hopefully its not like that this year

Mate that G481 june 2014 paper is deadly... Ive struggled with it, whilst the other papers are not so bad... Hopefully its not like that this year

What did you guys get on controlled assessment?

I got 10/10, 17/20 and 8/10 (35/40)

Hopefully an A is still 34+/-

I don't know why but I could never feel confident with studying for Physics. Thank God for M1 in maths as it really helped with certain concepts but my first exam is on the 19th May and I still need to learn Chapter 4 to 8 for Mechanics. I don't know the best way to prepare for mechanics. I only have a week and it seems that I am only getting marks in the definitions and simple areas. I'm barely scrapping an E.
At this rate, it's getting frustrating. I'm using the textbook to study even, maybe that's the problem- as I need the theory first I thought book first, past papers later but once I try the past papers, I get confused.

I'm doing OCR too, my god that exam board is rubbish. We haven't even been given the text books by m school so I'd assume that they aren't that great. I suggest working through the past papers with the mark scheme by your side, and making a list of all the topics/ questions you are dropping marks on, then take this list to your teacher, with the questions and getting them to work through the questions with you. There are only so many questions they can ask you so if you do past papers you should do ok.

I don't want to be that person but I am on track for an A (fingers crossed!) and I have really struggled with physics but don't worry, you can work your way up!.