Physics questions.. plz help..

[adnanj]

Assalam o alaikum.. anyone plz explain these questions to me.. would be really grateful..

http://www.xtremepapers.me/CIE/Cambridg ... 7_qp_2.pdf
Q9 C(i)

http://www.xtremepapers.me/CIE/Cambridg ... 7_qp_1.pdf
MCQ 2,25,30,39



http://www.xtremepapers.me/CIE/Cambridg ... 9_qp_1.pdf
MCQ 6 and 22

http://www.xtremepapers.me/CIE/Cambridg ... 7_qp_1.pdf
MCQ 28

 

[intelnehalem]

Q9 (c) (i
Use Boyle's law
P1V1= P2V2
6000x1.4x10^7= 30000x P2
solve for P2
P2= 2.8 x10^6

 

[intelnehalem]

MCQ 2 :
Since they are acting in different directions, the resultant can't be lesser than the vectors given!
So the answer is 10N which Is A
MCQ25:
Answer is B since motors involve a magnetic field, transformers involves a magnetic field,the video tape is also a form of magnetic storage (data is stored magnetically) so the answer has to be Power lead (B)
MCQ 30:
Answer is B
It is a parallel circuit. Since the resistors are equal, so current is equally divided (halved) from 1 A to 0.5A
MCQ39:
Answer is C
To get to 90 cps, 720-360-180-90, there are 3 half lives so 3 x2400 =7200 years
EDIT: MADE A CORRECTION

 

[intelnehalem]

O/N 2009 MCQ
Q6: Answer is A since the centripetal force (A) keeps the coin spinning with the table

Q22: Answer is B since this is a diverging lens and the object is virtual (on the same side as the object) and diminished.

 

[CaptainDanger]

Q9 c (i)

Do that using Gas Law, always when the temperature is constant
P1V1=P2V2

Put and solve...

MCQ 2,25,30,39

2.
The force can only be between the max and min values of the resultant force... As the answer A is not in between so its wrong..... Answer A....

25.
Drive motor, the transformer, the video tape.... All they contain magnetic material only the power lead does not so its the answer... B....


30.
First find the total resistance for the ones in parallel it becomes 6 into 6 / 6+6 = 3 Ω... Also the 3 Ω resistor so overall it becomes 3+3=6 Ω

Find the current in the circuit now
V=IR
6=I6
I=1 A

As the resistors are of equal resistance so current is equally separated... 1/2=.5 A B is the answer...

39.
You have to use this equation
A=a(1/2)^n
A is the activity of the source
a is the initial activity
n= number of half lives....

When you put it becomes
90=720(1/2)^n
(1/2)^n=90/720
(1/2)^n=1/8
(1/2)^n=(1/2)^3
n=3 (half lives)

Number of half lives needed for it to drop to 90 is 3 so 3 into 2400= 7200 yrs...

Posting the other solutions....

 

[CaptainDanger]

MCQ 28 Last paper you posted

Answer is B as the current increases resistance also increases stopping the current from further increase see the curve.... Already were answered I know but all that happened while I was typing so posted the answers anyway....

 

[adnanj]

Q9 (c) (i
Use Boyle's law
P1V1= P2V2
6000x1.4x10^7= 30000x P2
solve for P2
P2= 2.8 x10^6

Y aren't we subtracting 600 from 30000??? it says that 30000 is the volume of cylinder and air bag..??

 

[adnanj]

O/N 2009 MCQ
Q6: Answer is A since the centripetal force (A) keeps the coin spinning with the table

Q22: Answer is B since this is a diverging lens and the object is virtual (on the same side as the object) and diminished.

does diverging lens always result in a virtual image????

 

[adnanj]

MCQ 28 Last paper you posted

Answer is B as the current increases resistance also increases stopping the current from further increase see the curve.... Already were answered I know but all that happened while I was typing so posted the answers anyway....

thank u so much Captain,,

 

[adnanj]

intel thanks alot.... u people r doing great work May we all pass our exams with flying grades Ameen...

 

[abcde]

O/N 2009 MCQ
Q6: Answer is A since the centripetal force (A) keeps the coin spinning with the table

Q22: Answer is B since this is a diverging lens and the object is virtual (on the same side as the object) and diminished.

does diverging lens always result in a virtual image????

Yes

 

[intelnehalem]

Q9 (c) (i
Use Boyle's law
P1V1= P2V2
6000x1.4x10^7= 30000x P2
solve for P2
P2= 2.8 x10^6

Y aren't we subtracting 600 from 30000??? it says that 30000 is the volume of cylinder and air bag..??

Yeah so we have to find the pressure of 30000Cm3 of air in the cylinder which included the air from the air bag. So don't subtract 600, we have to find the total pressure of the whole cylinder Hope you understand!

 

[intelnehalem]

intel thanks alot.... u people r doing great work May we all pass our exams with flying grades Ameen...

Same to you mate ! We will pass with excellent results! Feel free to ask any question so we all can discuss and improve our knowledge !
All the best to you and everyone !