CBSE-XI-Physics

17: Light Waves

with Solutions - page 2
Qstn# ii-5 Prvs-QstnNext-Qstn
  • #5
    When light is refracted into a medium,
    (a) its wavelength and frequency increase
    (b) its wavelength increases but frequency remains unchanged
    (c) its wavelength decreases but frequency remains unchanged
    (d) its wavelength and frequency decrease
    digAnsr:   c
    Ans : (c) its wavelength decreases but frequency remains unchanged
    Frequency of a light wave, as it travels from one medium to another, always remains unchanged, while wavelength decreases.
    Decrease in the wavelength of light entering a medium of refractive index `` \mu `` is given by
    `` {\lambda }_{{\rm M}}=\frac{\lambda }{\mu },``
    `` where{\lambda }_{{\rm M}}=wavelengthinmedium``
    `` \lambda =wavelengthinvacuum``
    `` \mu =refractiveindex``
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