Please help me with my assignment.

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Hey guys,

I haven't done Physics last year, so I'm having a few doubts about my answers. Therefore, I was wondering if you guys can check my answers?

Thanks in advance.

here is the pdf file :   http://www.mediafire.com/?nm4x9dqc5px

My answers are :

Part A :
1. D
2. D
3. C or E?
4. C
5. D
6. C
7. D or E
8. C or D
9. A or B
10. D
11. A
12. A or B
13. A or B
14. A or B
15. B
16. A

Part B
1. E
2. C
3. C
4. D
5. D
6. A or B - I think it's B
7. B
8. A or D
9. C
10. A
11. C or E
12. C
13. E
14. A or B
15. A
16. E

[cara.mel]

Quickly going over the questions I see 'or' in
Part A:
3: Newton's 3rd law.
7: THink it through using F = ma
8: Same, also you know situations where velocity and acceleration are in different directions (eg circular motion)
12: Friction is independent of surface area
14: If you learn it the same way we do at Monash, rolling friction doesn't exist and there is only static and kinetic. Static friction is bigger => A

Part B:
6: Use F = ma to get a. Then use a = v/t
8: Imagine it as a triangle. The tension in the wire in the vertical component = W (or 1/2 W, tired and lazy, I'm a fail physicist), so therefore the total tension must be much bigger than W
11: F =( 0.4*12*9./cos 30
14: Constant speed => sum of forces = 0 => mg sin 30 = mu*N = mu * mg cos 30 => mu = sin 30/cos 30 = tan 30 (This is a handy thing to know in general)

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Thank you caramel .
Much appreciated.

Can anybody please go over the others ?