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प्रश्न
Why is exposure to X-rays injurious to health but not exposure to visible light, when both are electromagnetic waves?
उत्तर
X-rays have more penetrating power compared to visible light. As a result, they can penetrate the human body and can also damage the cells of the body. Prolonged exposure to X-rays can lead to cancer or genetic defects.
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संबंधित प्रश्न
Identify the part of the electromagnetic spectrum which is:
produced by bombarding a metal target by high speed electrons.
Use the formula λm T= 0.29 cm K to obtain the characteristic temperature ranges for different parts of the electromagnetic spectrum. What do the numbers that you obtain tell you?
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(a) Micro waves .
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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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(b) Ultraviolet rays
(c) γ -rays
Write one use of each of the above.
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-
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Name the radiation which can be detected by thermopile.
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Name one radiation having the wavelength longer than the wavelength of these radiations.
