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8 Feb 2012 14:05:25 IST

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The Photoelectric Effect!

Physics

Beam of photons: EM radiation or light

1) After imparting h energy to the electron where did the photon go?

2) Are momentum/Energy conserved in the process? And if they are then explain how?

3) What actually are free electrons and why do they exist?

4) What exactly is a photon? I mean what are the dimensions of the photon? is it a real particle? Can we picturise it?

5) How many packets of energy are contained in a ray of light from sun to earth?

6) If an electron is moving in space with some velocity 'v', what type of wave will be created by its motion?

7) Why the concept of intensity differ in wave and particle nature of EM radiation or light?

8) Is there energy associated with a matter wave? (de Broglie Wavelength)

9) How can you show energy is conserved in photoelectric effect?

10) How can there be momentum without mass? wrt. photon

11) The particle nature of life must effect our surroundings, for eg. the eye lens through which we see life, the walls, the rocks etc. Do light degredate these materials or it has no effect on them? Why these phenomenons are commonly not observed?

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Comments (7)

shivansh shrivastava

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Joined: 19 Jan 2012

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8 Feb 2012 17:16:45 IST

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Ph0t0ns r energy packets with zer0 rest mas,so they dnt exist aftr transfr of energy...they dnt really exist bt assumd to justify th particl properties of li8. . .

MIHIR K CHHAYA

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Joined: 30 Jan 2012

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9 Feb 2012 10:03:07 IST

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Plz. ask one by one

edison

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Joined: 19 Oct 2006

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13 Feb 2012 17:23:58 IST

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1) In photo electric effect photon is completely absorbed after imparting energy to the bound electron.2)Energy and momentum are always conserved.Remaining queries you raise in separate posts !!!

Vishal Mahuli

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11 Mar 2012 09:09:25 IST

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photon is just an energy packet which when colloids with electron.. transfers its energy n gets dissapeared... czz a mass can never exist without energy... energy n momentum are always conserved...... photon is a energy packet woth certain mass... but no charge.. it is nt deflected in electric n magentic fields.. it is deflected in gravitational fields.. definite dimensions cannot be found out since light behaves as particle nly during sum phenomena....

Vishal Mahuli

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11 Mar 2012 09:13:12 IST

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when an electron moves with a velcity V ... it is associated with MATTER WAVES... which can be given by De-Broglie's equation... Intensity is that property which intensifies a material.... in particles inorder to achieve that... No of particles colloiding per second must be more... in wave it is different.....

MAYANK KUMAR JHA

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11 Mar 2012 10:51:03 IST

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photon is a theoretical concept........... remember this........ wen we talk of energy transfer we talk it in terms of photons.........

MAYANK KUMAR JHA

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11 Mar 2012 11:19:08 IST

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1)photon vanished as it imparts energy 2)Momentum and energy both are conserved in this process,as before collision the photon had some momentum;(we dont know its mass ) after collision its momentum is zero and the body to which it transfers the energy has its momentum increased 3)Free electrons are unbounded electrons(not attached to any atom) and they do exist 4)Photon is dimensonless, it is an unreal particle and we cant picturise it5)The packets of energy depends on the size of the packet you are considering; as we know that the total energy incident on earth via solar radiation is of the order 10^18 joules. 6)Matter Wave 7)Concept of intensity remains same whatsoever be our context of consideration

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