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प्रश्न
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- Calculate the speed of the wave.
- Name the medium through which it is traveling.
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उत्तर
a. We know that,
v = f λ
Here it is given that c = 3 × 108 m/s
and, f = 500 MHz = 500 × 106 Hz
λ = 60 cm = 0.6 m
∴ v = (500 × 106 ) × (0.6) = 3 × 108 m/s
which is the same as the velocity of the e-m wave in vacuum or air.
b. The medium through which it is travelling is either air or vacuum.
संबंधित प्रश्न
A plane electromagnetic wave travels in vacuum along z-direction. What can you say about the directions of its electric and magnetic field vectors? If the frequency of the wave is 30 MHz, what is its wavelength?
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Name the region beyond the violet end of the spectrum called.
Name the waves used for taking photographs in dark.
X-ray from a Coolidge tube is incident on a thin aluminium foil. The intensity of the X-ray transmitted by the foil is found to be I0. The heating current is increased to increase the temperature of the filament. The intensity of the X-ray transmitted by the foil will be
(a) zero
(b) < I0
(c) I0
(d) > I0
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(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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