MCQ
When light is refracted into a denser medium,
  • A
    its wavelength and frequeny both increases
  • B
    its wavelength increase but freqnency remains unchanged
  • its wavelength decrease but freqnency remains unchanged
  • D
    its wavelength and freqnency both decrease.

Answer

Correct option: C.
its wavelength decrease but freqnency remains unchanged
c
$_1\mu_2 = \dfrac{v_1}{v_2} = \dfrac{v_{rarer}}{v_{denser}} \Rightarrow v_1 > v_2$3

$\Rightarrow v_1 > v_2$

$\Rightarrow \lambda_1 f_1 > \lambda_2 f_2$

Where $f$  is the frequency

when light goes from any rarer to any denser medium frequency remain unchanged.

$\therefore f_{1}=f_{2}=f$

$\Rightarrow \lambda_1 > \lambda_2$

hence wavelength decreases but frequency remains unchanged.

Option $C$ is correct.

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