The number of photo-electrons emitted per second from a metal surface increases when:
1. | The energy of incident photons increases. | 2. | The frequency of incident light increases. |
3. | The wavelength of the incident light increases. | 4. | The intensity of the incident light increases. |
1. | \(1.4\) eV | 2. | \(1.7\) eV |
3. | \(5.4\) eV | 4. | \(6.8\) eV |
The spectrum of radiation \(1.0\times 10^{14}\) Hz is in the infrared region.
The energy of one photon of this in joules will be:
1. \(6.62\times 10^{-48}\)
2. \(6.62\times 10^{-20}\)
3. \(\frac{6.62}{3}\times 10^{-28}\)
4. \(3\times 6.62\times 10^{-28}\)
1. | moves with one-fourth of energy as that of the initial energy. |
2. | moves with one-fourth of momentum as that of the initial momentum. |
3. | will be half in number. |
4. | will be one-fourth in number. |
The stopping potential for photoelectrons:
1. | does not depend on the frequency of the incident light. |
2. | does not depend upon the nature of the cathode material. |
3. | depends on both the frequency of the incident light and the nature of the cathode material. |
4. | depends upon the intensity of the incident light. |
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 stopping potential \(V\) for photoelectric emission from a metal surface is plotted along the \(Y\text-\)axis and the frequency \(\nu\) of incident light along the \(X\text-\)axis. A straight line is obtained as shown in the figure. Planck's constant is given by:
1. | the slope of the line. |
2. | the product of slope on the line and charge on the electron. |
3. | the product of intercept along the \(Y\text-\)axis and mass of the electron. |
4. | the product of the slope and mass of the electron. |
In an experiment on the photoelectric effect, the frequency \(f\) of the incident light is plotted against the stopping potential \(V_0.\) The work function of the photoelectric surface is given by:
(\(e\) is an electronic charge)
1. | \(OB\times e\) in eV |
2. | \(OB\) in volt |
3. | \(OA\) in eV |
4. | The slope of the line \(AB\) |
The stopping potential as a function of the frequency of the incident radiation is plotted for two different photoelectric surfaces \(A\) and \(B\). The graphs demonstrate that \(A\)'s work function is:
1. | Greater than that of \(B\). | 2. | Smaller than that of \(B\). |
3. | Equal to that of \(B\). | 4. | No inference can be drawn about their work functions from the given graphs. |