Particle nature and wave nature of electromagnetic waves and electrons can be shown by
(1) Electron has small mass, deflected by the metal sheet
(2) X-ray is diffracted, reflected by thick metal sheet
(3) Light is refracted and defracted
(4) Photoelectricity and electron microscopy
Momentum of a photon of wavelength is
(a) (b) Zero
(c) (d)
The photoelectric threshold wavelength for a metal surface is 6600 Å. The work function for this is
(1) 1.87 V
(2) 1.87 eV
(3) 18.7 eV
(4) 0.18 eV
1. | The stopping potential will decrease. |
2. | The stopping potential will increase. |
3. | The kinetic energy of emitted electrons will decrease. |
4. | The value of the work function will decrease. |
The maximum kinetic energy of photoelectrons emitted from a surface when photons of energy 6 eV fall on it is 4 eV. The stopping potential in volts is
(1) 2
(2) 4
(3) 6
(4) 10
A beam of light of wavelength \(\lambda\) and with illumination \(L\) falls on a clean surface of sodium. If \(N\) photoelectrons are emitted each with kinetic energy \(E\), then:
1. \(N \propto L \) and \(E \propto L \)
2. \(N \propto L \) and \(E \propto \frac{1}{\lambda}\)
3. \(N \propto \lambda\) and \(E \propto L \)
4. \(N \propto \frac{1}{\lambda}\) and \(E \propto \frac{1}{L}\)
Light of frequency v is incident on a substance of threshold frequency . The energy of the emitted photo-electron will be
(a) (b) h/v
(c) (d)
4 eV is the energy of the incident photon and the work function in 2eV. What is the stopping potential ?
(1) 2V
(2) 4V
(3) 6V
(4)
When radiation of wavelength is incident on a metallic surface, the stopping potential is 4.8 volts. If the same surface is illuminated with radiation of double the wavelength, then the stopping potential becomes 1.6 volts. Then the threshold wavelength for the surface is
(a) (b)
(c) (d)
If the energy of the photon is increased by a factor of 4, then its momentum
(1) Does not change
(2) Decreases by a factor of 4
(3) Increases by a factor of 4
(4) Decreases by a factor of 2