All Exams Test series for 1 year @ ₹349 only
Question

A student is performing an optics experiment using a glass slab. A laser beam is found to travel through the glass at a speed of \(2 \times 10^8\, m/s\). If the speed of light in air is \(3 \times 10^8\, m/s\), what is the refractive index of the glass slab ?

This question was previously asked in
UPTET 2026 Paper 2 Social Studies Question Paper (3-Jul-2026) (Shift 1)
The correct answer is

1.5

The refractive index of a medium is given by \(n = \dfrac{c}{v}\), where c is the speed of light in air and v is the speed of light in the medium.

Substituting values: \(n = \dfrac{3 \times 10^8}{2 \times 10^8} = 1.5\).

Therefore, the refractive index of the glass slab is 1.5.

Was this answer helpful?

Similar Questions

  1. The nature of image formed by a convex mirror for any object position is :


Important Questions from Refraction and Reflection

  1. A convex lens of focal length f will form a magnified real image of an object, if the object is placed.

  2. A ray of light travelling in the direction \(\frac{1}{2} (\hat i + \sqrt 3 \hat j)\) is incident on a plane mirror. After reflection it travels along the direction  \(\frac{1}{2} (\hat i - \sqrt 3 \hat j)\)  The angle of incidence is:

  3. Twinkling of stars is due to atmospheric

  4. An optical fibre has a core material of refractive index of 1.55 and cladding material of refractive index of 1.50. The numerical aperture of the fibre is

  5. The refracting angle of a prism is $A$. The refractive index of the material of the prism is $\frac{1+\cos A}{\sin A}$. The angle of minimum deviation is:
Need Expert Advice?
Upcoming Exams
MH SET
October 25, 2026
CTET
December 12, 2026
Test Series
UP TET img
Teaching
UPTET 2026 (Paper 1 & 2) Mock Test Series
257 Tests 16 Tests Free
2141 Attempts
4.6(18)
English, Hindi

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App