| 1 |
Platinum wire becomes white at a temperature of. |
- A. 1600<sup>o</sup>C
- B. 1300<sup>o</sup>C
- C. 1100<sup>o</sup>C
- D. 900<sup>o</sup>C
|
| 2 |
Light of 4.5 eV is incident on a Cesium surface and stopping potential is 0.25 eV, maximum K.E. of emitted electron is. |
- A. 4.5 eV
- B. 4.25 eV
- C. 4.75 eV
- D. 0.25 eV
|
| 3 |
The most refined form of matter is: |
- A. Smoke
- B. Light
- C. Ice
- D. Fog
|
| 4 |
The photoelectric effect predicts that light is made of |
- A. Photons
- B. Neutrons
- C. Protons
- D. None of these
|
| 5 |
Earth orbital speed is. |
- A. 10 km/s
- B. 20 km/s
- C. 30 km/s
- D. 40 km/s
|
| 6 |
If the energy of photon is 10 eV and work function is 5 eV, then the a value of stopping potential will be |
- A. 50 V
- B. 2 V
- C. 5 V
- D. 15 V
|
| 7 |
Platinum wire becomes yellow at a temperature of. |
- A. 900<sup> o</sup>C
- B. 1300<sup>o</sup>C
- C. 1600<sup>o</sup>C
- D. 500<sup>o</sup>C
|
| 8 |
The position has charge which is in magnitude equal to the charge on |
- A. Electron
- B. Proton
- C. <span style="font-weight: bold; color: rgb(106, 106, 106); font-family: arial, sans-serif; font-size: small;">β particle</span>
- D. All
|
| 9 |
Potassium Cathodes in photocell emit electrons for a light. |
- A. Visible
- B. Infra red
- C. Ultra violet
- D. X rays
|
| 10 |
Compton's effect is associated with |
- A. gamma rays
- B. Beta rays
- C. X rays
- D. Positive rays
|