AS Physics P1 MCQs Preparation Thread.

[Saad (سعد)]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s03_qp_1.pdf

help needed in question 4,8,15,20,22,40 ..... thanks lot

And finally, 20. Now this has to be the toughest question in the whole paper; I still haven't actually figured it out. But from what I understand; the boy applies a pressure which is a tenth of the atmospheric pressure atop the straw.

Which means that p0/10 is the pressure applied. You have to find the length of straw; basically, the h. And the density of the liquid to be pulled up is ρ. So...

p0/10 = ρgh.
h = p0/ρg10.

So the answer should be A... hey, that works! Figured it out, Al-Hamdulillah.

 

[Silent Hunter]

22: Calculate the spring constant of each spring. When a weight of W is applied, each spring gets W/3 of the load. The extension is x. Using Hooke's Law:

F = kx
k = F/x
k = (W/3)/x.

The spring constant, will, of course, remain the same no matter how many ways you attach it. With one spring removed, and a load of 2W, once again, you are asked for the extension. When the total load is 2W, each spring would get W. Once again use Hooke's Law:

F = kx
x = F/k
x = W/([W/3]/x)
=>x = 3x.

D is your answer.

Hope that helps insha' Allah!

JazakAllah bro one thing: the highlighted purple part : what if the springs were in series?

 

[Saad (سعد)]

JazakAllah bro one thing: the highlighted purple part : what if the springs were in series?

Parallel resistors are current dividers - series resistors have the same current.

Parallel springs are load dividers - series springs have the same load.

... I think. I sorta... forgot... how the series thing... works... But I'm pretty sure that's how it was... sorta.

 

[Silent Hunter]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s04_qp_1.pdf

6,17,26,31

 

[hussamh10]

13 - C
Condition for a couple is that the 2 forces should be equal and acting in opposite, parallel directions.

15 - A
You need to compare the lengths here and see which forces produce a closed triangle.

17 - D
Since the speed remains the same, the KE remains the same. Change in KE is zero.

31 - D
The resistance of a filament lamp increase with rise in temperature.

36 - A
The pd across the 2 resistors in the upper loop is 4/3 V. The pd across the resistor in the lower loop is 2/3 V. Difference is 2/3 A.

thak u very much

 

[Knight]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s04_qp_1.pdf

6,17,26,31

Q6; P=I^2/R
%age uncertanity in P = 2*(%age uncertanity in I) + %age uncertanity in R)
= 2*((0.05/2.50)*100) + 2
=6% ( C )

Q17; K.E=0.5*m*v^2
Let
K.E of Y=0.5mv^2
for Y having mass=m speed=v
Then
K.E of X=0.5*(2*m)*(v/2)^2
=0.5*2m*(v/4)
=0.5*m*v/2
=0.25*m*v
Therefore
K.E of Y = 0.5 the K.E of X ( A )

Q26; Intensity=E
E is directly proportional to A^2
so E will increase 4 times when amplitude A is increased to 2A but the surface area is halved so E will become 2E when amplitude is increased to 2A and surface area is decreased to 0.5S ( B )

Q31; I=nAve
as the wire used are made from the same material so n,v,e will be canceled in the ratio
(I in P)/(I in Q)=(area of P)/(area of Q)
=4 ( D )

Hope you understand it...............

 

[darknessinme]

is it always 10??? btw thnx

The 10s time estimate is a bit of general knowledge if you watch sports.
You could always work backwards by calculating the speed of the sprinter in all 4 choices. In A his speed would be too slow because it's jogging speed. C and D are too fast for any human to run. So B becomes the best estimate of his KE/speed.

 

[darknessinme]

when i do that, its coming 0.61, this is what im doing, please tell me whats wrong in this ( (1/10)x6 +1/100)

You need to take the reciprocal of the sum.

 

[Peter Check]

Travelling waves of wavelength 20 cm are created in the air columns in a closed pipe P and an
open pipe Q.In which pipe or pipes are stationary waves formed?
Answer was both P and Q. How is it Q, if it is open at both ends?? How can STATIONARY wave be formed if there is no superimposing of the waves???

 

[Peter Check]

Guys please I need help in questions 6,7,15,24 and 36 in http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w11_qp_11.pdf
for q6, why cant it be B? same for q7,why cant it be B?
I do not understand q15 .
And for 24 why in the world is A wrong!!

 

[Peter Check]

And finally, 20. Now this has to be the toughest question in the whole paper; I still haven't actually figured it out. But from what I understand; the boy applies a pressure which is a tenth of the atmospheric pressure atop the straw.

Which means that p0/10 is the pressure applied. You have to find the length of straw; basically, the h. And the density of the liquid to be pulled up is ρ. So...

p0/10 = ρgh.
h = p0/ρg10.

So the answer should be A... hey, that works! Figured it out, Al-Hamdulillah.

WHy is it p0/10 and not 10/p0

 

[Peter Check]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_s10_qp_11.pdf question 6. HOW DO WE DO IT!!!!!!

 

[Saad (سعد)]

WHy is it p0/10 and not 10/p0

How can the tenth part of Po be 10/Po? o.o;;;

 

[SalmanslK]

 

[fathimaash]

View attachment 11717

k
u knw dat 10N is in the centre of the rod
so 10N * 0.50m = Fsin30 * 1m
hence F = 10N.
is the answer C

 

[Manal1996]

can u provide me exact link?? i cant find october 2002 physics paper 1 marking scheme!

I'm sorry, i didnt check b4 i posted da link.That mark scheme doesnt seem to be available in that site as well as other sites i checked,I'm sorry.

 

[umarashraf]

I'm sorry, i didnt check b4 i posted da link.That mark scheme doesnt seem to be available in that site as well as other sites i checked,I'm sorry.

 

[Silent Hunter]

Q26; Intensity=E
E is directly proportional to A^2
so E will increase 4 times when amplitude A is increased to 2A but the surface area is halved so E will become 2E when amplitude is increased to 2A and surface area is decreased to 0.5S ( B )

Q31; I=nAve
as the wire used are made from the same material so n,v,e will be canceled in the ratio
(I in P)/(I in Q)=(area of P)/(area of Q)
=4 ( D )

Hope you understand it...............

THANKS ALOT .... just need lil bit more explanations on these thanks again

 

[smzimran]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s10_qp_11.pdf question 6. HOW DO WE DO IT!!!!!!

calculating the mass of the liquid,
it is (70 - 20) +/- (1+1)
= 50 +/- 2 [uncertainties are added because it is addition we are doing]

now density is mass / volume that means in this absolute uncertainties of mass and volume will be added

so
absolute uncertainty in density = absolute uncertainty in mass + absolute uncertainty in volume
absolute uncertainty in density = ( 2/50 ) + ( 0.6/10 )
absolute uncertainty in density = 0.10

uncertainty = absolute uncertainty * real value
uncertainty = 0.10 * 5 = 0.5

So, B is the answer!

 

[Peter Check]

calculating the mass of the liquid,
it is (70 - 20) +/- (1+1)
= 50 +/- 2 [uncertainties are added because it is addition we are doing]

now density is mass / volume that means in this absolute uncertainties of mass and volume will be added

so
absolute uncertainty in density = absolute uncertainty in mass + absolute uncertainty in volume
absolute uncertainty in density = ( 2/50 ) + ( 0.6/10 )
absolute uncertainty in density = 0.10

uncertainty = absolute uncertainty * real value
uncertainty = 0.10 * 5 = 0.5

So, B is the answer!

How is the real value 5?