1. | 2. | ||
3. | 4. |
1. | \(\frac{4}{A - 4}\) | 2. | \(\frac{A - 4}{4}\) |
3. | \(1\) | 4. | \(\frac{A + 4}{4}\) |
In the Davisson and Germer experiment, how can we increase the velocity of electrons emitted from the electron gun?
1. | increasing the filament current. |
2. | decreasing the filament current. |
3. | decreasing the potential difference between the anode and filament. |
4. | increasing the potential difference between the anode and filament. |
1. | \(1\) V | 2. | \(2.1\) V |
3. | \(3.1\) V | 4. | Zero |
The stopping potential of a photosensitive material is \(4~V\) when the wavelength of incident monochromatic radiation is \(\lambda.\) If the wavelength of incident radiation is doubled on the same photosensitive material, the stopping potential becomes \(V.\) The threshold wavelength of the photosensitive material will be:
1.
2.
3.
4.
1. | \(\dfrac{32}{11} \) | 2. | \(\dfrac{42}{11} \) |
3. | \(\dfrac{52}{11} \) | 4. | \(\dfrac{62}{11}\) |
The figure shows the variation in photoelectric current \((i)\) with voltage \((V)\) between the electrodes in a photocell for two different radiations. If \(I_a\) and \(I_b\) are the intensities of the incident radiation and \(\nu_a\) and \(\nu_b\) their respective frequencies, then:
1. | \(I_a>I_b,~ \nu_b<\nu_a\) | 2. | \(I_a<I_b, ~\nu_b>\nu_a\) |
3. | \(I_a>I_b,~ \nu_b=\nu_a\) | 4. | \(I_a<I_b, ~\nu_b<\nu_a\) |
1. | the stopping potential will be \(0.2\) volts. |
2. | the stopping potential will be \(0.6\) volts. |
3. | the saturation current will be \(6\) mA. |
4. | the saturation current will be \(18\) mA. |
1. | \(\frac{h^{2} m}{2 \lambda^{2}}\) | 2. | \(\frac{2 h m^{2}}{\lambda^{2}}\) |
3. | \(\frac{h^{2} \lambda^{2}}{2 m}\) | 4. | \(\frac{h^{2}}{2 m \lambda^{2}}\) |