Q. No.The work function of a metal is \(h\nu_0.\) Light of frequency \(\nu\) falls on this metal. The photoelectric effect will take place only if:
1. \(\nu\geq \nu_0\)
2. \(\nu>2\ \nu_0\)
3. \(\nu<\nu_0\)
4. \(\nu<\nu_0/2\)
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
| Assertion (A): | The work function of aluminium is \(4.2~\text{eV}\). Emission of electrons will not be possible if two photons, each of energy \(2.5~\text{eV}\), strike an electron of aluminium. |
| Reason (R): | For photoelectric emission, the energy of each photon should be greater than the work function of aluminium. |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
Why does the wave theory of light fail to explain the photoelectric effect?
| 1. | The photoelectric effect does not occur if the frequency of light is below a certain threshold, regardless of its intensity. |
| 2. | The maximum kinetic energy of the emitted electrons is unaffected by the intensity of the radiation. |
| 3. | There is no observable time delay between the radiation striking the surface and the emission of electrons. |
| 4. | All of the above factors. |
As the intensity of incident light increases,
| 1. | photoelectric current increases. |
| 2. | photoelectric current decreases. |
| 3. | kinetic energy of emitted photoelectrons increases. |
| 4. | kinetic energy of emitted photoelectrons decreases. |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
1. orange light
2. yellow light
3. green light
4. violet light
If the frequency of incident radiations is doubled, then which of the following will increase?
1. Kinetic energy of the electron
2. Photoelectric current
3. Stopping potential
4. Both (1) & (3)
The figure below shows the variation of photocurrent \((i)\) with anode potential \((V).\) The three curves are due to:
| 1. | variation in the colour of light |
| 2. | variation in the frequency of light |
| 3. | variation in the intensity of light |
| 4. | variation in the photoelectric material |
1. Potassium
2. Rubber
3. Plastic
4. Solid hydrogen
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
\((\text{take}~h=6.6\times 10^{-34}~ \text{J-s};~1~\text{eV}=1.6\times 10^{-19}~\text{J})\)
1. \(8.0\times10^{14} ~\text{Hz }\)
2. \(8.0\times10^{16}~\text{ Hz} \)
3. \(8.0\times10^{18} ~\text{Hz}\)
4. \(8.0\times10^{19}~ \text{Hz }\)
© 2026 GoodEd Technologies Pvt. Ltd.