ENTRANCE TEST – 2010 Multiple Questions and Answers.
Exercise Questions ::
PHYSICS
16. | The minimum frequency below which no electron is emitted from the metal surface is called |
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| A. | High frequency |
| B. | Low frequency |
| C. | Threshold frequency |
| D. | Resonance frequency |
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18. | The life time of an electron in an excited state is about 10-8 s. What is its uncertainty in energy during this time? |
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| A. | 1.05 x 10-41 J |
| B. | 1.05 x 10-26 J |
| C. | 1.15 x 1010 J |
| D. | 2.19 x 10-40 J |
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