• 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)

Physics: Post your doubts here!

Messages
1,824
Reaction score
949
Points
123

Increasing the variable resistor's resistance will make more PD fall on the variable resistor and less resistance on the fixed resistor! so Voltmeter reading will decrease..

But The ammeter reading will stay unchanged.. since the voltage in parallel circuits is same.. so according to the formula V=IR .. if R remains same I will remain same too.

so Answer should be C.
 
Messages
1,824
Reaction score
949
Points
123
Someone please please help me understand the following questions:
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w05_qp_1.pdf
Qn no. 28, 33, 34
syed1995

x=lambda*D/a
(Lambda/2*D)/2a
x=1/4*Lambda*D/a
so answer should be.. 0.75. A

33

Two Equations

1) R = pL/A
2) Strain = F/A

If strain increases area decreases... according to 2.

Then according to 1 .. If A decreases R increases. So answer is D.

34 ..

draw a line from origin to each of the points... whichever has the lease gradient will give you the answer.. since gradient of the graph is I/V .. and resistance is V/I.. so we need the least gradient. as resistance is 1/gradient so Answer is C
 
Messages
128
Reaction score
112
Points
53
x=lambda*D/a
(Lambda/2*D)/2a
x=1/4*Lambda*D/a
so answer should be.. 0.75. A

33

Two Equations

1) R = pL/A
2) Strain = F/A

If strain increases area decreases... according to 2.

Then according to 1 .. If A decreases R increases. So answer is D.

34 ..

draw a line from origin to each of the points... whichever has the lease gradient will give you the answer.. since gradient of the graph is I/V .. and resistance is V/I.. so we need the least gradient. as resistance is 1/gradient so Answer is C
Thanks a lot brother
For no. 33, isnt it strain = extension/original length?
 
Messages
1,824
Reaction score
949
Points
123
hey help me in oct nov 09-28,21,13,12

12B

R1=R2 is obvious since the force downwards will be same..

38WQz.png


So force is R1=2*T1Cos(Theta) and R2=2*T2Cos(Theta) .. as R1=R2 .. As Theta is greater in 1 more force will be required. so T1>T2.

13 No Clue.

21 it's kinda logical.. If you draw a straight line from origin to P.. you will see that the strain energy coming as 0.10 J.. and will also see that there is some area above the line you drew as well.. so there will be more a little more energy than 0.1... so answer is C.

28 No Clue.
 
Messages
14
Reaction score
3
Points
3
A particle of mass 2m and velocity v strikes a wall.
The particle rebounds along the same path after colliding with the wall. The collision is inelastic.
What is a possible change in the momentum of the ball during the collision?
A mv B 2mv C 3mv D 4mv

answer is C.. plz someone explain
The collision is inelastic so the speed of the ball after rebounding will be less than v but greater than 0. the answer cant be A or B because the change has to be greater than 2mv since it changes direction. d also cant be because it would make the collision elastic thus c as rebound speed is 0.5v which is in possible range
 
Messages
325
Reaction score
215
Points
53
Messages
325
Reaction score
215
Points
53
Ty, I still don't understand 14, 19
You have to understand projectile motion to understand 14. The vertical component of the velocity at the highest point during a parabolic trajectory will be 0, and its horizontal component will stay the same throughout.
In 19, all you have to do is put in numbers into the formulas I've given you. You're given the pressure, which is F/A. They want you to find the density. Density=m/v. To get m, you'll need to divide F/g (g is a constant). To get V, you'll need to multiply A with the height, which is given in the question.
 
Top