Physics: Post your doubts here!

[Swoorup]

momentum = force/second
OR momentum=mV-mU
Hence it becomes=MV-m(-u) which is equal to mv+mu
for question two seperation = 2 times the radius and the rest work out yourself

NOTE: Momentum is made for velocity in same direction but if an object bounce back off the final velocity becomes negative so they add up. You can take any direction as a reference point: either U or V since momentum is generally not in negative form!

 

[zenyatales]

help ? thank you !
it's not too hard...

In question 3c iii , cannot we move the pivot closer to the centre to increase the max weight of the student ?
it doesn't say so in the ms.

thanks for the time !

 

[akbararshad]

Assalam-o-alaikum
i have a conusion regarding the relation between amplitude and intensity of a wave.
like, i know its I:amp^2. but when the amplitude is halved what happens to the intensity? Do we have to divide it by underroot 2 or by 4?

 

[Swoorup]

Intensity is 1/4th

 

[markskoop]

May june 11 P23 question number 6 "b" need help...
some one plz reply soon

 

[akbararshad]

Intensity is 1/4th

thanks alot

 

[Oliveme]

Please answer these physics questions and explain?
1) A uniform rod has a weight of 14N. It is pivoted at one end and held in a horizontal position by a thread tied to its other end. The thread makes angle of 50 degrees with the horizontal. Calculate -
a) the moment of the weight of the rod about the pivot.
b) the tension T in the thread required to hold the rod horizontally.

2) A uniform plant of weight 120N rests on two stools. Stool A is 0.5m from the end of the plank and stool B is 1m away from the end of the plank. A weight of 80N is placed on the plank, midway between the stools. Calculate:
a) the force acting on the stool at A,
b) the force acting on the stool at B.

3) A force of 36N acts at an angle of 55degrees to the vertical. The force moves its point of application by 64cm in the direction of the force. Calculate the work done by -
a) the horizontal component of the force
b) the vertical component of the force.

Thanks.

 

[Assassin5415]

Paper 1 Doubts !!

Assalam-o-Aleikum everyone
and greetings to evryone

I have doubts in Phy P1 and as im practicing them atm, Ill have more of them coming up in time
as for now, can anyone explain:

M/J 2006 - Ques 9, 31, 33, 34, 36
O/N 2006 - Ques 9, 10, 11, 14, 21, 25, 27

Thanks in advance

P.S. I dont knw how to post the link here using the 'URL' tab, hope u ppl can manage with that :$

 

[Silent Hunter]

Assalam-o-Aleikum : just wanted to ask a general question : From where can we find complete formula list for Physics AS levels? any website?

 

[unique840]

Re: Paper 1 Doubts !!

Assalam-o-Aleikum everyone
and greetings to evryone

I have doubts in Phy P1 and as im practicing them atm, Ill have more of them coming up in time
as for now, can anyone explain:

M/J 2006 - Ques 9, 31, 33, 34, 36
O/N 2006 - Ques 9, 10, 11, 14, 21, 25, 27

Thanks in advance

P.S. I dont knw how to post the link here using the 'URL' tab, hope u ppl can manage with that :$

june 06: ans 9= max velocity is at mean position and zero at max height. so the distance - time graph will be as shown in the attachment. the points A,B,C,D will be as shown. so the velocity at lowest point of motion is at D

 

[tanmaydube]

http://www.xtremepapers.com/CIE/International A And AS Level/9702 - Physics/9702_s06_qp_2.pdf

Q5) a),b) and c)

THANKS A LOT!

 

[unique840]

http://www.xtremepapers.com/CIE/International A And AS Level/9702 - Physics/9702_s06_qp_2.pdf

Q5) a),b) and c)

THANKS A LOT!

a) the loading and unloading graph overlaps each other showing no permanent deformation so the change is elastic.

b) w= area under graph
f=kx
area of trapezium = 1/2 [(x2 - x1) (f1 + f2)]
1/2 [ (x2 - x1) (kx1 + kx2)]
1/2 * k { x2^2 - x1^2}

 

[unique840]

http://www.xtremepapers.com/CIE/International A And AS Level/9702 - Physics/9702_s06_qp_2.pdf

Q5) a),b) and c)

THANKS A LOT!

c) energy = work done
total energy = work done by both the springs
extension 1 = 4.5 - 1.5 = 3 cm
extension 2 = 4.5 + 1.5 = 6 cm
energy = 1/2 * k(x2^2 - x1^2) + 1/2 * k(x2^2 - x1^2)
1/2 * 1600 (0.06^2 - 0.045^2) + 1/2 * 1600 (0.03^2 - 0.045^2)
1.26 + (-0.9)
0.36 J
0.36 = 1/2 * m * v^2
(0.36 * 2)/0.85 = v^2
v=0.92 m/s

 

[unique840]

Re: Paper 1 Doubts !!

Assalam-o-Aleikum everyone
and greetings to evryone

I have doubts in Phy P1 and as im practicing them atm, Ill have more of them coming up in time
as for now, can anyone explain:

M/J 2006 - Ques 9, 31, 33, 34, 36
O/N 2006 - Ques 9, 10, 11, 14, 21, 25, 27

Thanks in advance

P.S. I dont knw how to post the link here using the 'URL' tab, hope u ppl can manage with that :$

june 06
33) 500:1000 = 1:2
2000:1000 = 2:1
500 ohms resistor will consume 4 V. at X there will be a potential of 4V
2000 ohms resistor will consume 8 V. at Y there will be a potential of 8 V
so the difference of p.d between X and Y is 8-4 = 4 V

36) all the resistors have equal resistances. both the branches has resistance of 2R. in the next circuit, only the arrangement is changed but still both the branches has 2R. so the brightness will be the same as before

 

[unique840]

Re: Paper 1 Doubts !!

Assalam-o-Aleikum everyone
and greetings to evryone

I have doubts in Phy P1 and as im practicing them atm, Ill have more of them coming up in time
as for now, can anyone explain:

M/J 2006 - Ques 9, 31, 33, 34, 36
O/N 2006 - Ques 9, 10, 11, 14, 21, 25, 27

Thanks in advance

P.S. I dont knw how to post the link here using the 'URL' tab, hope u ppl can manage with that :$

nov 06
21) pressure = density*g*h
17.5 * 10^6 = (830*9.8*x) + (1000*9.8*(2000-x))
x= 1260 ~= 1270

 

[shockwaveman]

please help me with the Phy paper 1 past years M/J/07 ques 40...M/J/08 ques 6 and 24...i also need the explanation...thanks...

 

[sweetiepie]

As and Alevel definations

viewtopic.php?f=26&t=12353

check these may help u all

 

[pennies]

how is A the answer?

 

[pennies]

how do u find an expression for the emf? the answer is supposed to be C...

 

[pennies]

how come C is the answer?