Question

When a light ray travels from one medium to another medium, which of the following statement(s) is/are correct?

• A. Frequency remains unchanged
• B. Speed of light changes
• C. Wavelength of light changes
• D. Light rays bend towards the normal if the rays travel from rarer to denser medium.

Answer 1

Answer: (A), (B), (C), (D)

Light rays bend towards the normal if the rays travel from rarer to denser medium.

From Snell's law,
$\Rightarrow \frac{v_1}{v_2}=\frac{n_2}{n_1}=\frac{{\lambda }_1}{{\lambda }_2}$
where, $n\to$ refracting index

We know that speed of light in a denser medium is lower than that in rarer medium.
So, speed and wavelength of light changes, but frequency remains the same because it depends only on the source.

From law of refraction, light bends towards the normal if $n_2>n_1$ as shown in the figure.


Hence, all options are correct.