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प्रश्न
Answer briefly.
Why light waves travel in a vacuum whereas sound waves cannot?
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उत्तर
Light waves are electromagnetic waves that can travel in a vacuum where sound waves travel due to the vibration of particles of the medium. Without any particles present (like in a vacuum) no vibrations can be produced. Hence, the sound wave cannot travel through the vacuum.
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संबंधित प्रश्न
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- State its one use.
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Name the region beyond the violet end of the spectrum called.
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For a given material, the energy and wavelength of characteristic X-rays satisfy
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(b) E(Mα) > E(Lα) > E(Kα)
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(d) λ(Mα) > λ(Lα) > λ(Kα).
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(Use Planck constant h = 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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(Use Planck constant h = 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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