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 |
The work function of a metal surface is φ = 1.5 eV. If a light of wavelength 5000 Å falls on it, then the maximum K.E. of the ejected electron will be:
1. | 1.2 eV | 2. | 0.98 eV |
3. | 0.45 eV | 4. | 0 eV |
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
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
A metallic surface is exposed to two radiations separately, one of wavelength 4000 Å and the other of 8000 Å. If the work function of metal is 1 eV, then the ratio of maximum kinetic energies of photoelectrons is nearly equal to:
1. | \(\frac{32}{11} \) | 2. | \(\frac{42}{11} \) |
3. | \(\frac{52}{11} \) | 4. | \(\frac{62}{11}\) |
The photosensitive material's work function is 4.0 eV. The longest wavelength of light that can cause a substance's photoelectric emission is approximately:
1. 3100 nm
2. 966 nm
3. 31 nm
4. 310 nm