Radiation of energy \(E\) falls normally on a perfectly reflecting surface. The momentum transferred to the surface is:
(\(c\) = velocity of light)

1. \(E \over c\) 2. \(2E \over c\)
3. \(2E \over c^2\) 4. \(E \over c^2\)

Subtopic:  Particle Nature of Light |
 73%
Level 2: 60%+
NEET - 2015
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A certain metallic surface is illuminated with monochromatic light of wavelength \(\lambda\). The stopping potential for photoelectric current for this light is \(3V_0\). If the same surface is illuminated with a light of wavelength \(2\lambda\), the stopping potential is \(V_0\). The threshold wavelength for this surface for the photoelectric effect is:
1. \(6\lambda\) 2. \(4\lambda\)
3. \(\dfrac{\lambda}{4}\) 4. \(\dfrac{\lambda}{6}\)
Subtopic:  Einstein's Photoelectric Equation |
 82%
Level 1: 80%+
NEET - 2015
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Which of the following figures represent the variation of the particle momentum and the associated de-Broglie wavelength?

1.   2.
3.   4.  
Subtopic:  De-broglie Wavelength |
 88%
Level 1: 80%+
NEET - 2015
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For photoelectric emission from certain metals, the cutoff frequency is \(\nu.\) If radiation of frequency \(2\nu\) impinges on the metal plate, the maximum possible velocity of the emitted electron will be:
(\(m\) is the electron mass)

1. \(\sqrt{\dfrac{h\nu}{m}}\) 2. \(\sqrt{\dfrac{2h\nu}{m}}\)
3. \(2\sqrt{\dfrac{h\nu}{m}}\) 4. \(\sqrt{\dfrac{h\nu}{2m}}\)
Subtopic:  Einstein's Photoelectric Equation |
 84%
Level 1: 80%+
AIPMT - 2013
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In the photoelectric emission process from a metal of work function 1.8 eV, the kinetic energy of most energetic electrons is 0.5 eV. The corresponding stopping potential is:

1.  1.3 V

2.  0.5 V

3.  2.3 V

4.  1.8 V

Subtopic:  Photoelectric Effect: Experiment |
 75%
Level 2: 60%+
AIPMT - 2011
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Light of two different frequencies, whose photons have energies of \(1\) eV and \(2.5\) eV respectively, illuminates a metallic surface whose work function is \(0.5\) eV successively. The ratio of maximum speeds of emitted electrons will be:
1. \(1:2\)
2. \(1:1\)
3. \(1:5\)
4. \(1:4\)
Subtopic:  Einstein's Photoelectric Equation |
 77%
Level 2: 60%+
AIPMT - 2011
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Electrons used in an electron microscope are accelerated by a voltage of 25 kV. If the voltage is increased to 100 kV, then the de-Broglie wavelength associated with the electrons would:

1.  decrease by 2 times

2.  decrease by 4 times

3.  increase by 4 times

4.  increase by 2 times

Subtopic:  De-broglie Wavelength |
 75%
Level 2: 60%+
AIPMT - 2011
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A source S1 is producing 1015 photons per sec of wavelength 5000 Å. Another source S2 is producing 1.02×1015 photons per second of wavelength 5100 Å. Then, (power of S2)/(power of S1) is equal to:

1. 1.00

2. 1.02

3. 1.04

4. 0.98

Subtopic:  Photoelectric Effect: Experiment |
 75%
Level 2: 60%+
AIPMT - 2010
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Monochromatic light of wavelength 667 nm is produced by a helium-neon laser. The power emitted is 9mW. The number of photons arriving per second on average at a target irradiated by this beam is:
1. 9 x 1017

2. 3 X 1016

3. 9 x 1015

4. 3 X 1019

Subtopic:  Photoelectric Effect: Experiment |
 79%
Level 2: 60%+
AIPMT - 2009
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The number of photoelectrons emitted for the light of a frequency ν (higher than the threshold frequency ν0) is proportional to:
1. ν -ν0
2. threshold frequency (ν0)
3. intensity of light
4. frequency of light (ν)
Subtopic:  Photoelectric Effect: Experiment |
 79%
Level 2: 60%+
AIPMT - 2009
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