Physics: Post your doubts here!

[zenyatales]

sorry i can't help. only done AS. hope smone writes soon

 

[unique840]

http://www.xtremepapers.com/CIE/International%20A%20And%20AS%20Level/9702%20-%20Physics/9702_s09_ms_2.pdf

Paper 21, Please Explain Question 5b

path difference is 28 cm.
take the first n last frequency and the calculate the corresponding lambda and path difference. then insert the values of 'n' and 'n/2' which determines the max n min. so there are 2 min

 

[ching293]

People!!!!!!!!!!!!! I have a doubt in O/N 2010 paper 43, question 3a(i). how do we find the displacement when there's no value given for "t" in the given equation!!
HELP....i'm dead in this question!!!!!!! :O:

i think from the equation, amplitude is 4.0cm, do the displacement is 8.0cm

 

[waspzalachenko]

Wud anybody help me, please!! Well, i got a problem with a quesion.. It's QN. 25.. May/june 2004, paper one..
I'd be very glad if smbdy'd help me...

 

[rz123]

^well its A as the q point is stationary , its at the maximum displacement position. resting position u can say. and P is downwards as the wave profile behind is downwards. the wave pattern behind the point p is negative !

 

[DaEconomist]

http://www.xtremepapers.com/CIE/Interna ... _qp_12.pdf

Question 21

any help will be greatly appreciated.

thanks

 

[anahita16]

http://www.xtremepapers.com/CIE/International%20A%20And%20AS%20Level/9702%20-%20Physics/9702_w09_qp_12.pdf

Question 21

any help will be greatly appreciated.

thanks

To find the percentage of length that contracted, you need to get the ratio of the extended length to the original length, and that's strain.strain= dL/L

Young Modulus=stress/strain
=F/A by dL/L

Replacing
2.0 × 10^11=(20/pie(2.5×10^-4))/ (dL/L)
dL/L = 5.1×10^-4
Percentage=5.1×10^-4 ×100
=5.1×10^-2
Ans B

 

[DaEconomist]

http://www.xtremepapers.com/CIE/Interna ... 8_qp_1.pdf

question 27

any help would be great.

thanks

 

[anahita16]

Distance between maxima = Half wavelength
so lamda/2 = 15mm
lamda=30mm=.030m
microwave is an electromagnetic wave, meaning that its speed is 3.0*10^8.
v=f(lamda)
f=v/ (lamda)
=3×10^8 / 0.03
= 1.0×10^10 Hz
Ans C 1.0 × 10^10 Hz

 

[DaEconomist]

thanks again!

 

[anahita16]

You're welcome again!

 

[DaEconomist]

http://www.xtremepapers.com/CIE/Interna ... 3_qp_1.pdf

question 10

help please.

thanks.

 

[DaEconomist]

http://www.xtremepapers.com/CIE/Interna ... 3_qp_1.pdf

question 22

can the 'resistor's in parallel' rule be used in this

any help would be great

thanks

 

[slayers]

Hey, Can anyone post expected question for physcics practical papers 33/34 and Physics paper 2 ?

 

[rz123]

^^22. Its D because you have removed one spring and the weight and now when you put a 2W weight so the extension would have to be more then twice as u took off some weight before. hence the value 3x will be correct.

 

[ching293]

can anyone show me which finger pointing which side for left hand rule in this question? Thanks

paper42/june 2010

 

[slayers]

I am having problem with following question./?
Please solve it with explanation...
Physics 9702(paper2) may/june 2007 question 3c ii and 4d i

 

[XPFMember]

Assalamoalaikum!!

can anyone show me which finger pointing which side for left hand rule in this question? Thanks

paper42/june 2010

Remember when using Fleming's Left Hand Rule, Second finger is the CONVENTIONAL current direction! so the electron movement is opp. to the conventional current..
in this case since the direction of electron movement is left, the direction of conventional current will be to the right...
now try it, you'll get the movement towards QR

 

[ching293]

Assalamoalaikum!!

can anyone show me which finger pointing which side for left hand rule in this question? Thanks

paper42/june 2010

Remember when using Fleming's Left Hand Rule, Second finger is the CONVENTIONAL current direction! so the electron movement is opp. to the conventional current..
in this case since the direction of electron movement is left, the direction of conventional current will be to the right...
now try it, you'll get the movement towards QR

Thank you so much, very helpful

 

[babycry]

guys help needed,

http://xtremepapers.net/CIE/index.php?d ... _qp_13.pdf

question 9 from oct/nov 2010 paper 13:

9 A body, initially at rest, explodes into two masses M1 and M2 that move apart with speeds v1 and v2 respectively.
What is the ratio v1/v2?



thanks