1. | \(\mathrm{Na}\) only | 2. | \(\mathrm{Cs}\) only |
3. | Both \(\mathrm{Na}\) and \(\mathrm{K}\) | 4. | \(\mathrm{K}\) only |
In a photoelectric experiment, blue light is capable of ejecting a photoelectron from a specific metal while green light is not able to eject a photoelectron. Ejection of photoelectrons is also possible using light of the colour:
1. yellow
2. red
3. violet
4. orange
Light of a frequency of \(1.5\) times the threshold frequency is incident on a photosensitive material. What happens to the photoelectric current when the frequency is cut in half and the intensity is doubled?
1. | four times | 2. | one-fourth |
3. | zero | 4. | doubled |
The work function of the photosensitive material is \(4.0~\text{eV}\). The longest wavelength of light that can cause photoelectric emission from the substance is (approximately):
1. \(3100~\text{nm}\)
2. \(966~\text{nm}\)
3. \(31~\text{nm}\)
4. \(310~\text{nm}\)