Physics: Post your doubts here!

[Most_UniQue]

well i have been taught to think of current as a living thing and that wires are passageways where current walks freely in. resistors are a like narrow tunnels funneling the current to go in as "a single line" so if there is a less narrow route the current will go through it which is in this case S2 as it has no resistance

Oh tnx! A new thing which I learnt so its always like this?

 

[Most_UniQue]

Y does the current avoid B in 2nd? And what do you mean 2nd row current will always go through less resistance route?

and fr 5th one , y isnt it 3kw? Why doesnt it avoid B as u had mentioned?

 

[Unicorn]

and fr 5th one , y isnt it 3kw? Why doesnt it avoid B as u had mentioned?

because switch S2 is open

 

[Unicorn]

Oh tnx! A new thing which I learnt so its always like this?

yeah

 

[Unicorn]

Oh tnx! A new thing which I learnt so its always like this?

even check this page just scroll down
http://www.physicsclassroom.com/Class/circuits/u9l4b.cfm

 

[jsg]

http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s07_qp_2.pdf
http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s07_ms_2.pdf

Help needed in Q3 part c ... !!

 

[Most_UniQue]

because switch S2 is open

Oh ya so if it was closed then we wud avoid B ? and it would be 3 kw ryt?

 

[Most_UniQue]

even check this page just scroll down
http://www.physicsclassroom.com/Class/circuits/u9l4b.cfm

Nice site!! Tnx!

 

[Peter Check]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w11_qp_22.pdf

qestion 4 part- 4, shouldnt the charge keep moving down!!! because its not negative, so despite increase in force, charge will go from positive to negative!!

 

[Peter Check]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_s10_qp_23.pdf 2 a ii, how is it 2.08V, can anyone show me??

 

[Hassi123]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s10_qp_23.pdf 2 a ii, how is it 2.08V, can anyone show me??

there is no 2 aii :/

 

[A.ELWY 7]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s10_qp_23.pdf 2 a ii, how is it 2.08V, can anyone show me??

um first of all it was question 1 a ii....ok and yes the answer is 2.08 because as u answered in the first part a change would be +or- 0.0205...so maximum vlaue must be 2.05 + 0.0205=2.0705..then he said in the question that there is +or - 1digit..so 1 digit means 0.01 so 2.0705+0.01=2.0805..wish u understood.

 

[xxxtoughxxx]

heyy can some1 help me wiv Q15 here hasnt da height decresed by half not 1/4??

 

[fatima 007]

Hello. can anyone post the link from o-levels book of the electromagnetic ball release system. My sir said to review it for tomorrow's paper.

 

[xxxtoughxxx]

Can someone please help me in question 4c

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s10_qp_22.pdf
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s10_ms_22.pdf

I understand that the lowest sound would be at an antinode but then why is the wavelength 1.8m not 2.4m

well an antinode is 1/4 of a wavelengh right? so given that l=45cm the antinode is 45 cm and wavelengh is 0.45x4=1.8 m aand u calculate the frequency from v=fxwavelengh

 

[raamish]

How is P=Fv derived?
A question from pastpaper:Explain why a cyclist travelling at a constant speed is not making this trnasformation. Explain what transformations are taking place?

 

[Sandhya Mahat]

Plz anyone help me understand how Q. 2c of Oct/Nov 2011(21) is done..

 

[Sandhya Mahat]

Plz anyone help me understand how Q. 2c of Oct/Nov 2011(21) is done..

 

[RGBM211]

Show that a 100W lamp connected to a mains supply of 240V will have the same current as a 5W car lamp connected to a 12V? ans- current in both is 2.4A

can someone explain =D

 

[xxxtoughxxx]

How is P=Fv derived?
A question from pastpaper:Explain why a cyclist travelling at a constant speed is not making this trnasformation. Explain what transformations are taking place?

power is the rate of doin work nd work is fxd then p=(fxd)/t and d/t is v then p=fv......and post da whole question 4 da cyclist