Physics: Post your doubts here!

[ruby_fern]

check at
http://physics-ref.blogspot.com/2014/11/9702-november-2009-paper-22-worked.html

Jazaakallahu khairan

 

[Llamas]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s09_qp_4.pdf

Question ten, part B.
Can someone please tell me exactly what is happening, what the 'gain' is, and what formula is used for the result?

 

[Llamas]

check qu 27 at
http://physics-ref.blogspot.com/2014/10/physics-9702-doubts-help-page-4.html

Thank you!!

 

[princess Anu]

check qu 27 at
http://physics-ref.blogspot.com/2014/10/physics-9702-doubts-help-page-4.html

Help please

 

[princess Anu]

Q14 shouldn't ans be C?

 

[The Sarcastic Retard]

Q14 shouldn't ans be C?

c = f * lambda
Wavelength is inversely proportional to f so we are asked to find greatest wavelength of UV radiation so we have to use lowest frequency of UV.
Hence 10^(-7) is the shortest " f " & c = 10^(8)
f = 10^(8-(-7))=10^(15)

 

[Llamas]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_w09_qp_41.pdf

Question 5, part B2, please!

 

[Bba321]

second one is explained at
http://physics-ref.blogspot.com/2014/09/9702-november-2009-paper-42-worked.html

Thanks

 

[princess Anu]

.

 

[salvatore]

check at
http://physics-ref.blogspot.com/2015/03/physics-9702-doubts-help-page-90.html

Perfect! Thanks xD

 

[Armybrat007]

Casn someone please explain how we eliminate v in two equation whileCalculating the e/m ratio of the electron using cathode-anode voltage?

 

[manya]

can someone help me with this. i dont understand y the answer is not A

 

[Dream.Eater]

can someone help me with this. i dont understand y the answer is not A

Is the answer C?

 

[princess Anu]

when two waves are in phase their path difference has to be O? or can it be an integral multiple of wavelength?

 

[princess Anu]

what should be the effect and why?

 

[The Sarcastic Retard]

can someone help me with this. i dont understand y the answer is not A

You may have not checked the answer correctly, it has to be A. You are correct.

 

[The Sarcastic Retard]

when two waves are in phase their path difference has to be O? or can it be an integral multiple of wavelength?

Yes it is always zero when the waves are in phase.

 

[The Sarcastic Retard]

View attachment 51289 what should be the effect and why?

-suchal

 

[manya]

Is the answer C?

yes, it is C.

 

[manya]

You may have not checked the answer correctly, it has to be A. You are correct.

i wish but i checked again and it is still not the answer. it is question no. 5 of may june 2005.
here is the link
http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s05_qp_1.pdf
http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s05_ms_1.pdf