# If the kinetic energy of the particle is increased to 16 times its previous value, the percentage change in the de-Broglie wavelength of the particle is: 1. 25 2. 75 3. 60 4. 50

Subtopic:  De-broglie Wavelength |
72%
From NCERT
AIPMT - 2014
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For photoelectric emission from certain metals, the cutoff frequency is $\nu$. If radiation of frequency 2$\mathrm{\nu }$ impinges on the metal plate, the maximum possible velocity of the emitted electron will be:
(m is the electron mass)

1. $\sqrt{\mathrm{h\nu }/\mathrm{m}}$

2. $\sqrt{2\mathrm{h\nu }/\mathrm{m}}$

3. $2\sqrt{\mathrm{h\nu }/\mathrm{m}}$

4. $\sqrt{\mathrm{h\nu }/\left(2\mathrm{m}\right)}$

Subtopic:  Einstein's Photoelectric Equation |
82%
From NCERT
AIPMT - 2013
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The wavelength λe of an electron and λP of a photon of the same energy E are related by:
1. λP ∝ λe
2. λP ∝ $\sqrt{}$ ${\lambda }_{e}$
3. λP ∝ $\frac{1}{\sqrt{}}$ ${\lambda }_{e}$
4. λP ∝ λe2
Subtopic:  De-broglie Wavelength |
61%
From NCERT
AIPMT - 2013
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A 200 W sodium street lamp emits yellow light of wavelength 0.6 $\mathrm{\mu m}$. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is:

1. $1.5×{10}^{20}$

2. $6×{10}^{18}$

3. $62×{10}^{20}$

4. $3×{10}^{19}$

Subtopic:  Photoelectric Effect: Experiment |
70%
From NCERT
AIPMT - 2012
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An $\mathrm{\alpha }$-particle moves in a circular path of radius 0.83 cm in the presence of a magnetic field of 0.25 Wb/m2. The de-Broglie wavelength associated with the particle will be:

$2.$ $0.1$ $\stackrel{\mathrm{o}}{\mathrm{A}}$

$3.$ $10$ $\stackrel{\mathrm{o}}{\mathrm{A}}$

$4.$ $0.01$ $\stackrel{\mathrm{o}}{\mathrm{A}}$

Subtopic:  De-broglie Wavelength |
56%
From NCERT
AIPMT - 2012
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A radioactive nucleus of mass M emits a photon of frequency $\nu$ and the nucleus will recoil. The recoil energy will be:

1.  $\frac{{\mathrm{h}}^{2}{\mathrm{\nu }}^{2}}{2{\mathrm{Mc}}^{2}}$

2.  zero

3.  $\frac{\mathrm{h\nu }}{\mathrm{c}\sqrt{2\mathrm{M}}}$

4.  $\frac{\mathrm{c}\sqrt{2\mathrm{M}}}{\mathrm{h\nu }}$

Subtopic:  De-broglie Wavelength |
65%
From NCERT
AIPMT - 2011
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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 |
73%
From NCERT
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 |
74%
From NCERT
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 |
73%
From NCERT
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%
From NCERT
AIPMT - 2010
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