Physics MCQs for NEET — Practice Questions with Answers

The relationship between the refractive indices of different media follows the principle of reversibility of light. For four different transparent media, the product of the refractive indices \( n_{41} \times n_{32} \times n_{21} \) is the same as the reciprocal of \( n_{14} \) because \( n_{ij} = \frac{1}{n_{ji}} \). Therefore, \( n_{41} \times n_{32} \times n_{21} = \frac{1}{n_{14}} \).

A plane mirror always produces an image that is virtual, erect, and of the same size as the object. Therefore, the magnification produced by a plane mirror is +1. This means the size of the image is equal to the size of the object.

$ use \;ho = \sqrt {h_1 h_2 }$

When two thin lenses of focal lengths \( f_1 \) and \( f_2 \) are placed in contact, the power of the combination (P) is given by the sum of the powers of the individual lenses. Power is the reciprocal of the focal length (in meters). Therefore, \( P = rac{1}{f_1} + rac{1}{f_2} = rac{f_1 + f_2}{f_1 f_2} \).

Light is scattered by the droplets in the fog. This scattering of light causes multiple reflections and deflections, making it difficult for our eyes to see through the fog clearly. This phenomenon is known as Rayleigh scattering.

$ use , shift = x \left( { 1 - {1 \over n }} \right) $

$ Hera , n = { h \over h'} $ $ \therefore h' = 2.0 -0.2 = 1.8 $ $ \therefore {2 \over 1.5 } = { 20 \over 18} = 1.11 = n $