Q6 of 25 Page 10

Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in a vacuum is 3 × 108 m s–1. ( CBSE 2011)

We know that:

Refractive index of glass = (Speed of light in air (or vacuum))/(Speed of light in glass)


1.50 = (3×108)/(Speed of light in glass)


Or, Speed of light in glass =  = 2×108 ms-1


Thus, the speed of light in glass is 2×108 ms-1 (or 2×108 m/s).

More from this chapter

All 25 →
4

What does the negative sign in the value of magnification produced by a mirror indicates about an image? ( CBSE 2009)

 5

Define 1 Dioptre of power of a lens. ( CBSE 2010)

 7

An object is placed at a distance of 30 cm from a concave lens of focal length 15 cm. List four characteristics (nature, position, etc.) of the image formed by the lens. ( CBSE 2013, 2012)

 8

List four characteristics of the images formed by plane mirrors. ( CBSE 2008)