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प्रश्न
Answer briefly.
What are radio waves?
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उत्तर
- Radio waves are produced by accelerated motion of charges in a conducting wire. The frequency of waves produced by the circuit depends upon the magnitudes of the inductance and the capacitance.
- Thus, by choosing suitable values of the inductance and the capacitance, radio waves of the desired frequency can be produced.
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संबंधित प्रश्न
Identify the part of the electromagnetic spectrum which is suitable for radar system used in aircraft navigation.
Identify the part of the electromagnetic spectrum which is:
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Give a reason for the following:
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Name the phenomenon which shows the quantum nature of electromagnetic radiation.
State an additional use of the X-rays waves
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(a) Visible.
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(b) < I0
(c) I0
(d) > I0
Find the maximum potential difference which may be applied across an X-ray tube with tungsten target without emitting any characteristic K or L X-ray. The energy levels of the tungsten atom with an electron knocked out are as follows.
| Cell containing vacancy | K | L | M |
| Energy in keV | 69.5 | 11.3 | 2.3 |
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- Arrange these wavelengths in ascending order of their magnitude.
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