What physical quantity is the same for X-rays of wavelength \(10^{−10} m\), red light of wavelength \(6800 Å\) and radio waves of wavelength \(500\ m\)?
What physical quantity is the same for X-rays of wavelength \(10^{−10} m\), red light of wavelength \(6800 Å\) and radio waves of wavelength \(500\ m\)?
Solution and Explanation
The speed of light \((3 \times 10^8\ m/s)\) in a vacuum is the same for all wavelengths. It is independent of the wavelength in the vacuum.
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Concepts Used:
Electromagnetic Spectrum
The term used by scientists to describe the entire range of light that exists is the electrostatic spectrum. Light is a wave of alternating electric and magnetic fields. The propagation of light doesn't vary from waves crossing an ocean. Like any other wave, light also has a few fundamental properties that describe it. One is its frequency. The frequency is measured in Hz, which counts the number of waves that pass by a point in one second.
The electromagnetic waves that your eyes detect are visible light and oscillate between 400 and 790 terahertz (THz). That’s several hundred trillion times a second.