A photon of energy 3.4 eV is incident on a metal having a work function of 2 eV. The maximum K.E. of photo-electrons is equal to:
1. | 1.4 eV | 2. | 1.7 eV |
3. | 5.4 eV | 4. | 6.8 eV |
For photoelectric emission from certain metals, the cutoff frequency is \(\nu\). If radiation of frequency \(2\nu\) impinges on the metal plate, the maximum possible velocity of the emitted electron will be:
(\(m\) is the electron mass)
1. | \(\sqrt{\frac{h\nu}{m}}\) | 2. | \(\sqrt{\frac{2h\nu}{m}}\) |
3. | \(2\sqrt{\frac{h\nu}{m}}\) | 4. | \(\sqrt{\frac{h\nu}{2m}}\) |
When monochromatic photons of wavelength \(4000\) Å are incident on the metal plate of work function \(2.1\) eV, what will be the stopping potential for the photocurrent?
1. | \(1\) V | 2. | \(2.1\) V |
3. | \(3.1\) V | 4. | Zero |
The correct graph between the maximum energy of a photoelectron \(\left(K_{max}\right)\) and the inverse of the wavelength \(\left(\frac{1}{\lambda}\right)\) of the incident radiation is given by the curve:
1. | \(A\) | 2. | \(B\) |
3. | \(C\) | 4. | None of these |
A certain metallic surface is illuminated with monochromatic light of wavelength λ. The stopping potential for photoelectric current for this light is 3Vo. If the same surface is illuminated with light of wavelength 2λ, the stopping potential is Vo.
The photoelectric effect's threshold wavelength for this surface is?
1. 6λ
2. 4λ
3. λ/4
4. λ/6
The work functions for metals A, B, and C are respectively 1.92 eV, 2.0 eV, and 5 eV. According to Einstein's equation, the metals that will emit photoelectrons for a radiation of wavelength 4100 Å is/are:
1. None
2. A only
3. A and B only
4. All the three metals
The variation of the kinetic energy \((K)\) of photoelectrons as a function of the frequency \((f)\) of the incident radiation is best shown by:
1. | 2. | ||
3. | 4. |
1. 1:2
2. 1:1
3. 1:5
4. 1:4
In an experiment of the photoelectric effect, the wavelength of incident radiation is . The wavelength of incident radiation is reduced to rd of initial value and the maximum kinetic energy of photoelectron is observed to be n times the previous value.
What will be the threshold wavelength for the metal plate?
1. \(\frac{n-1}{n-3} \lambda \)
2. \(\frac{n}{n-3} \lambda \)
3. \(\frac{n-3}{n-1} \lambda \)
4. \(\frac{n+1}{n-3} \lambda\)
A photosensitive metallic surface has a work function of hν0. If photons of energy 2hν0 fall on this surface, the electrons come out with a maximum velocity of 4 × 106 m/s. When the photon energy is increased to 5hν0, then the maximum velocity of photoelectrons will be:
1. 2 ×107 m/s
2. 2 × 106 m/s
3. 8 × 105 m/s
4. 8 × 106 m/s