MCQOPTIONS
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MCQOPTIONS
This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Physics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Calculate the kinetic energy of a photoelectron (in eV) emitted on shining light of wavelength 6.2 10-6 m on a metal surface. The work function of the metal is 0.1 eV. |
| A. | 10 eV |
| B. | 0.1 eV |
| C. | 0.01 eV |
| D. | 1000 eV |
| Answer» C. 0.01 eV | |
| 2. |
For a photosensitive surface, the work function is 3.3 10-19 J. Calculate the threshold frequency. |
| A. | 15 10<sup>14</sup> Hz |
| B. | 25 10<sup>14</sup> Hz |
| C. | 5 10<sup>14</sup> Hz |
| D. | 55 10<sup>14</sup> Hz |
| Answer» D. 55 10<sup>14</sup> Hz | |
| 3. |
The stopping potential in an experiment on the photoelectric effect is 1.5 V. What is the maximum kinetic energy of the photoelectrons emitted? |
| A. | 1.5 eV |
| B. | 3 eV |
| C. | 4.5 eV |
| D. | 6 eV |
| Answer» B. 3 eV | |
| 4. |
The maximum kinetic energy of a photoelectron is 3 eV. What is the stopping potential? |
| A. | 0 V |
| B. | 3 V |
| C. | 9 V |
| D. | 12 V |
| Answer» C. 9 V | |
| 5. |
The stopping potential in photoelectric emission does not depend upon the frequency of the incident radiation. |
| A. | True |
| B. | False |
| Answer» C. | |
| 6. |
If the intensity of the radiation incident on a photo-sensitive plate is doubled, how does the stopping potential change? |
| A. | Increases |
| B. | Decreases |
| C. | No effect |
| D. | Infinite |
| Answer» D. Infinite | |
| 7. |
How does retarding potential vary with the frequency of light causing photoelectric effect? |
| A. | Infinite |
| B. | Zero |
| C. | Decreases |
| D. | Increases |
| Answer» E. | |
| 8. |
If the frequency of the incident radiation is equal to the threshold frequency, what will be the value of the stopping potential? |
| A. | 0 |
| B. | Infinite |
| C. | 180 V |
| D. | 1220 V |
| Answer» B. Infinite | |
| 9. |
If the intensity of incident radiation in a photo-cell is increased, how does the stopping potential vary? |
| A. | Increases |
| B. | Remains the same |
| C. | Decreases |
| D. | Infinite |
| Answer» C. Decreases | |
| 10. |
Two beams, one of red light and the other of blue light, of the same intensity are incident on a metallic surface to emit photoelectrons. Which emits electrons of greater frequency? |
| A. | Both |
| B. | Red light |
| C. | Blue light |
| D. | Neither |
| Answer» D. Neither | |