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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निम्नलिखित गद्यांश की सप्रसंग व्याख्या कीजिए :
‘‘पुर्ज़े खोलकर फिर ठीक करना उतना कठिन काम नहीं है, लोग सीखते भी हैं, सिखाते भी हैं, अनाड़ी के हाथ में चाहे घड़ी मत दो पर जो घड़ीसाज़ी का इम्तहान पास कर आया है उसे तो देखने दो । साथ ही यह भी समझा दो कि आपको स्वयं घड़ी देखना, साफ़ करना और सुधारना आता है कि नहीं । हमें तो धोखा होता है कि परदादा की घड़ी जेब में डाले फिरते हो, वह बंद हो गई है, तुम्हें न चाबी देना आता है न पुर्ज़े सुधारना तो भी दूसरों को हाथ नहीं लगाने देते इत्यादि ।’’
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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.