General Science Gk Questions
37. |
The working of the quartz crystal in the watch is based on the |
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- A. Johnson effect
- B. Edison effect
- C. Piezo electric effect
- D. Photoelectric effect
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38. |
What is the unit for measuring the pitch or frequency of sound? |
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- A. Decibel
- B. Hertz
- C. Coulomb
- D. Hum
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39. |
In fireworks, the green flame is produced because of |
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- A. Potassium
- B. Sodium
- C. Mercury
- D. Barium
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40. |
The type of glass is used in making lenses and prism is |
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- A. Jena glass
- B. Flint glass
- C. Pyrex glass
- D. Soft glass
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