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प्रश्न
A wave has wavelength 50 Å.
- Name the wave.
- State its speed in vacuum.
- State its one use.
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उत्तर
- An electromagnetic wave having a wavelength 50 Å is an X-ray. They have a wavelength in the range of 0.1 Å to 100 Å.
- The speed of an electromagnetic wave (here X-ray) in a vacuum is 3x108 m/s.
- Since, they are stopped by bones, they are used for the detection of fractures in bones, teeth, etc., and for diagnostic purposes such as CAT scans in medical science.
संबंधित प्रश्न
A radio can tune in to any station in the 7.5 MHz to 12 MHz band. What is the corresponding wavelength band?
Give a reason for the following:
Long-distance radio broadcasts use short-wave bands. Why?
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
If the operating potential in an X-ray tube is increased by 1%, by what percentage does the cutoff wavelength decrease?
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
An X-ray tube operates at 40 kV. Suppose the electron converts 70% of its energy into a photon at each collision. Find the lowest there wavelengths emitted from the tube. Neglect the energy imparted to the atom with which the electron collides.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
Name any two electromagnetic waves which have a frequency higher than that of violet light. State one use of each.
An e.m. wave exerts pressure on the surface on which it is incident. Justify.
Write two uses of the following radiation.
X-rays
Which is the correct ascending order of wavelengths?
