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Question
A wave has wavelength 50 Å.
- Name the wave.
- State its speed in vacuum.
- State its one use.
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Solution
- 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.
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Assertion (A): Ultraviolet radiations is scattered more as compared to the microwave radiations.
Reason (R): Wavelength of ultraviolet radiation is more than the wavelength of microwave radiation.
Below is an incomplete table showing the arrangement of electromagnetic spectrum in the increasing order of their wavelength. Complete the table:
| Gamma ray | X - ray | UV rays | Visible rays | Infrared | A | Radio waves |
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