- 1(current)
Q. No.A photo-cell is illuminated by a source of light, which is placed at a distance \(d\) from the cell. If the distance becomes \(\frac{d}{2}\), then the number of electrons emitted per second will be:
1. same
2. four times
3. two times
4. one-fourth
1. work function of material
2. intensity of incident radiation
3. frequency of incident radiation
4. wavelength of incident radiation
The wavelength of light in the visible region is about \(550\) nm (average wavelength) for yellow-green colour. Three materials with work functions are given as Al (\(4.28\) eV), Cu (\(4.65\) eV) and Na (\(2.75\) eV). From which of these photosensitive materials, can you build a photoelectric device that operates with visible light?
1. Al
2. Cu
3. Na
4. none of the above
1. \(2\) V
2. \(3.2\) V
3. \(4.2\) V
4. \(5.2\) V
1. \(\frac{\lambda{P}}{h c} f\)
2. \(\frac{2\lambda{P}}{h c} f\)
3. \(\frac{\lambda{P}}{h c} f e\)
4. \(\frac{2\lambda{P}}{h c} f e\)
| 1. | \(V_0 /2\) | 2. | \(V_0 \) |
| 3. | \(4V_0 \) | 4. | \(2V_0 \) |
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
| 1. | be tripled. |
| 2. | be more than tripled. |
| 3. | be less than tripled. |
| 4. | become one third. |
| 1. | a straight line with a positive intercept on the \(x\)-axis (frequency) |
| 2. | a straight line with a positive intercept on the \(y\)-axis (kinetic energy) |
| 3. | a parabola |
| 4. | a hyperbola |
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Q. No.
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