Which rays are used in LASER?
Correct answer: A. Electromagnetic radiation
- A. Electromagnetic radiation
- B. Black body radiation
- C. Alpha rays
- D. Beta rays
Explanation
LASER stands for Light Amplification by Stimulated Emission of Radiation. It is made up of very intense, monochromatic, highly focused, and uniform beams of light. Electromagnetic radiation from the far-infrared to the ultraviolet region can be used in a LASER. Electromagnetic waves travel at the same speed in free space - 3×108 m/s. Their wavelengths and frequencies differ. The electromagnetic spectrum, in order of increasing frequency (decreasing wavelength), is:Radio waves > Microwaves > Infrared Radiation > Visible Light > UV Rays > X-rays> Gamma Rays.
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About Atomic Spectra
Atoms emit or absorb light at specific wavelengths because electrons occupy quantized energy levels and change levels by absorbing or releasing photons. The topic covers emission and absorption spectra, spectral series, hydrogen’s line spectrum, energy-level transitions, and the relation between wavelength, frequency and photon energy.
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