• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

AS Physics P1 MCQs Preparation Thread.

Messages
121
Reaction score
32
Points
38
At O a maximum is observed. Now, u r moving the detector up to X. A MINIMUM is observed at X since the question says no signal is detected here. So what do we know? At minima, the path difference of two waves falling on a point is (n+ 1/2)*lambda, where n is the number of orders of dark fringes. So at X, n=0 so path difference is 1/2*lambda. Hope it helped, dudette (I believe ;) )
 
Messages
4,609
Reaction score
3,903
Points
323
well we know about specific heat capacity from Olevels. nothing new. but still it should be clearly mentioned in the syllabus. Thanks for the answer.

true bro ... but still ..... they should have given one extra mark for this.... :p .... me also got it wrong the first time :p ;) ... lets hope they do not give anything out of the given syllabus this time :)
 
Messages
121
Reaction score
32
Points
38
1st question:
Now, for 3 springs in parallel, the extension is x. So the extension for a SINGLE spring would have been 3x for a load of W.
NOW, for 2 springs in parallel the extension for a load of W = 3x/2
now, FOR A LOAD OF 2W the extension for those 2 springs would quite obviously be 2* 3x/2= 3x

2nd question:
It said the current was DECREASED UNIFORMLY. So, we can take the AVERAGE current during that time period. So charge = average current * time (do the calculation now from here :) )

Hope I could help you boss.
 
Messages
222
Reaction score
25
Points
38
1st question:
Now, for 3 springs in parallel, the extension is x. So the extension for a SINGLE spring would have been 3x for a load of W.
NOW, for 2 springs in parallel the extension for a load of W = 3x/2
now, FOR A LOAD OF 2W the extension for those 2 springs would quite obviously be 2* 3x/2= 3x

2nd question:
It said the current was DECREASED UNIFORMLY. So, we can take the AVERAGE current during that time period. So charge = average current * time (do the calculation now from here :) )

Hope I could help you boss.

Thanks :)
 
Messages
318
Reaction score
328
Points
73
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s09_qp_1.pdf
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s09_er.pdf
Q18 can someone please explain?

Does anyone know what q/m ratio is? It is related to nuclear physics. theres a question m/j 2007 q40 to answer which you have to know the particle which has the lowest q/m ratio.
i dont know if its included in our syllabus but i didnt see it anywhere.
please hep someone!!!!!
 
Messages
971
Reaction score
532
Points
103
well we know about specific heat capacity from Olevels. nothing new. but still it should be clearly mentioned in the syllabus. Thanks for the answer.
Yeah, from O-levels. :p We didn't study it in AS level and there's a good possibility people forgot it. Good thing I have Chemistry too, because we learn a formula relating to heat capacity with that. :p
 
Messages
76
Reaction score
17
Points
18
This is an inelastic collision but momentum would remain conserved.
so the total momentum before collision equals momentum after collision
so (3m x v) - (2m x v) (- sign is because they are moving in the opposite direction)= (3m + 2m) vfinal
mv=(4m)vfinal
hence vfinal=v/4
Untitled.jpg
 
Messages
3,063
Reaction score
1,831
Points
173
don't know what you are doing for Q18
as for me i am using equation output power/ input power *100=x
so 4M/x *100=80 so input power is 5M
P=IV so 5M/25K =200A

20
answer is B beacuse when you leave your clothes out to dry do they stay as same temprature they came out of the washing machine or do they feel cooler? They feel cooler due to evaporation

21
total pressure is 17.5M and using equation P=hdg
we have 2 liquids so pressure of water + pressure of oil is 17.5
height of oil is x and water is 2000-x
so 17.5M=(2000-x)*1000*9.81 + x*830*9.81 solve to get x= 1271

30
electric field is constant

was using p=v/i too but mayb some odr w0rking... for Q 30 shouldnt we be using da formula E=V/d ?? that way answer comes as B...
umm Q no 27 too :)
thnx a lot
 
Messages
971
Reaction score
532
Points
103
Q11)

Momentum has to be conserved, so.

Initial momentum = Final momentum

Initial is 0 and at final, they move in opposite directions, so..

0 = M1V1 - M2V2

M2V2 = M1V1

V1/V2 = M2/M1

Q36) In this, the first 10 Ohm resistor which is perpendicular from X to Y is in parallel with the 3 other 10 Ohm resistors (total = 30), so the combined resistance is the inverse of:

(1/10) + (1/30) = 7.5 Ohm which is between 1 and 10 Ohm.

Q37)

X is connected directly with the voltmeter so if the potentiometer is at point X, the voltmeter will always read 4.0 V. If you move to Y, then you can apply the potentiometer formula to calculate the current.

V = 4 * (10/20) = 2 V

So At X, V = 4
At Y, V = 2

B is the only graph that suits this. :)
 

XPFMember

XPRS Moderator
Messages
4,555
Reaction score
13,290
Points
523
Wa Alaikumus Salam wa rahmatulahi wa barakatuh,
i found this explanation in the other thread n it seems logical to me
Ans; B
X is in tension as it is opposing the weight of the horizontal bar and the foce W...Y is aso in tension as it is opposing W..Z is in compression as it is between a force from X and a force of Y and W
actually i dont seem to understand this..

can u elaborate
 
Messages
971
Reaction score
532
Points
103
actually i dont seem to understand this..

can u elaborate
An outer edge (i.e. X and Y) will always stretch (tension) while an inner edge (Z) will always compress (compression), so the answer is B. There was a question which utilized this concept in one of the P2 papers, but I don't remember which one it was exactly.
 

XPFMember

XPRS Moderator
Messages
4,555
Reaction score
13,290
Points
523
An outer edge (i.e. X and Y) will always stretch (tension) while an inner edge (Z) will always compress (compression), so the answer is B. There was a question which utilized this concept in one of the P2 papers, but I don't remember which one it was exactly.
stretch = tension...oh..now i get it...

AsSalamoALaikum wr wb n jazakAllah
 
Messages
373
Reaction score
1,091
Points
153
Q11)

Momentum has to be conserved, so.

Initial momentum = Final momentum

Initial is 0 and at final, they move in opposite directions, so..

0 = M1V1 - M2V2

M2V2 = M1V1

V1/V2 = M2/M1

Q36) In this, the first 10 Ohm resistor which is perpendicular from X to Y is in parallel with the 3 other 10 Ohm resistors (total = 30), so the combined resistance is the inverse of:

(1/10) + (1/30) = 7.5 Ohm which is between 1 and 10 Ohm.

Q37)

X is connected directly with the voltmeter so if the potentiometer is at point X, the voltmeter will always read 4.0 V. If you move to Y, then you can apply the potentiometer formula to calculate the current.

V = 4 * (10/20) = 2 V

So At X, V = 4
At Y, V = 2

B is the only graph that suits this. :)
Jazakallah. Thank you very much for help. May Allah bless you. :)
 
Messages
373
Reaction score
1,091
Points
153
Q11)

Momentum has to be conserved, so.

Initial momentum = Final momentum

Initial is 0 and at final, they move in opposite directions, so..

0 = M1V1 - M2V2

M2V2 = M1V1

V1/V2 = M2/M1

Q36) In this, the first 10 Ohm resistor which is perpendicular from X to Y is in parallel with the 3 other 10 Ohm resistors (total = 30), so the combined resistance is the inverse of:

(1/10) + (1/30) = 7.5 Ohm which is between 1 and 10 Ohm.

Q37)

X is connected directly with the voltmeter so if the potentiometer is at point X, the voltmeter will always read 4.0 V. If you move to Y, then you can apply the potentiometer formula to calculate the current.

V = 4 * (10/20) = 2 V

So At X, V = 4
At Y, V = 2

B is the only graph that suits this. :)
There is just one problem, though. For question 37, the answer is A.
 
Messages
971
Reaction score
532
Points
103
Q9)

Initial m = Final m

mv + 0 = 2mx (note: after the bodies stick, their masses combine. Let their combined speed be 'x').
mv = 2mx
x = v/2 (m cancel out)

Since the initial momentum is mv, the final momentum must be the same, so its mv also.

K.E after is given by,

0.5 * (2m) * (v/2)^2
= mv^2/4

So A. :)

Q10)

Change in momentum = final m - initial m

Since after impact the direction changes, final m is -mu

= -mu - mu
= -2mu

Q14) My advice for these type of questions would be to use some sort of fake value for something which isn't known. Here we can't use a fake value for u or v since we have to find their ratios which is fixed, but we can use a fake value for the height to make calculations easier. One of my friends asked me this earlier, so I drew a diagram - link. Let me know if you don't get anything.

Q31)

Q = I * t
Q = 10 * 1 = 10C

(Note that the area is given for no apparent reason, there's no area in the charge formula).

1 electron = 1.6 * 10^-19 C
x electron = 10C

x = 6.3 * 10^19 electrons.

Q35) Total R = 0.588
Total V = IR = 0.588 * 5 ~2.94

Where the ammeter is, the voltage will be 2.94 and R is 2, so I would be given by V/R = 2.94/2 = 1.47 which is 1.5A to 1 dp.
 
Top