AS Physics P1 MCQs Preparation Thread.

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ppl postn dis fr da 2nd tm!!!!!!
Nov 2005

Q3: D... E=kg m^2 s^-2..power=kg m^2 s^-3...V=P/I...so kg m^2 s^-3 A^-1= V
Q9: D...u must understand it as it came from the equation m1u1 + m2u2 = m1v1 + m2v2..as the total INITIAL momentum before collision is equal to the total final momentum after collison..same meaning but different words
Q11: A...in vaccum..the only force acting is gravity..so only XV as it is vertical
Q15: A...potential energy increases as height increases..and he didnt say it fell to the ground so C is wrong
Q20: work done is equal to the strain energy which is the area under the graph so B is the answer
Q28: slits seperation is inversely proportional to the fringe spacing..so slit space is doubled so spce is halfed so 3/2=1.5..then wavelength is proportional to fringe seperation..so wavelength halfed hence fring seperation halfed so 1.5/2= 0.75 so A
wish i helped
 
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10: use F=ma
60/30= 2m/s^2 then use v=u + at

3 - 2*0.5=2

13:
only top of belt has tension so only use half diameter as this only top half provides tension

torque on Q= 3 therefore 3 / (0.1 /2 ) =60

60 * (0.15 /2)

14 [not sure abt this one]

19:
d=m/v and p=f/a

break down the equation to get d = m/ a*h

15200= f/a and f=mg so m=f/g therefore (f/g)/(a*h) whoch gives f/gah

and using 15200= f/a f is 15200a so 15200a/9.81 * a* 0.8 = 1936 which is closest to B

31
rate of energy transfer is power and P=I^2 R
which is C

hope it helped
 
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may june 2005
7,10,13,16,22,39

7:
apparently the answer is B because gravity always acts downwards

10:
You need to learn newtons laws nothing to explain here

13:
moe.png
I have marked for you the forces causing clockwise moments and anti clockwise moment

so therefore 5*2 + 2*10 - 3*20 =30 anticlockwise

16:
power in this case is the gradient and gradient is steepest between 2-3 secs
so 40-10/3-2 =30

22 [don't know my self]

39: answer is B revise nuclear physics
 
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10: use F=ma
60/30= 2m/s^2 then use v=u + at

3 - 2*0.5=2

13:
only top of belt has tension so only use half diameter as this only top half provides tension

torque on Q= 3 therefore 3 / (0.1 /2 ) =60

60 * (0.15 /2)

14 [not sure abt this one]

19:
d=m/v and p=f/a

break down the equation to get d = m/ a*h

15200= f/a and f=mg so m=f/g therefore (f/g)/(a*h) whoch gives f/gah

and using 15200= f/a f is 15200a so 15200a/9.81 * a* 0.8 = 1936 which is closest to B

31
rate of energy transfer is power and P=I^2 R
which is C

hope it helped
Could you explain 13 a bit more in detail? I mean, I don't get why you use half of the diameter.
 
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Could you explain 13 a bit more in detail? I mean, I don't get why you use half of the diameter.

because full diameter is only used when we take couple/torque thingy :p ;) here as the lower side of belt is slag... so only upwards force acts on one side.... creating moment :p so maybe thats why we use half diameter = the radius :p ;) :)
 
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7:
apparently the answer is B because gravity always acts downwards

10:
You need to learn newtons laws nothing to explain here

13:
View attachment 12069
I have marked for you the forces causing clockwise moments and anti clockwise moment

so therefore 5*2 + 2*10 - 3*20 =30 anticlockwise

16:
power in this case is the gradient and gradient is steepest between 2-3 secs
so 40-10/3-2 =30

22 [don't know my self]

39: answer is B revise nuclear physics
Thank you very much (the moment question was well explained)
 
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