# Lakhmir Singh Solutions Class 10 Physics Chapter 5: Refraction of Light

This chapter focuses on the bending of light on passing from one medium to another. The phenomenon is known as refraction. Students will get to know the causes of refraction, the concept of optical density, optically rarer, and optically denser medium. Why and how a change in speed of light causes refraction is studied under the following cases:

• When the light goes from a relatively rarer medium to a denser medium
• When the light goes from relatively denser to rarer medium
• The case of light going from air into the glass and again into the air
• The case of light normally falling on a glass slab

Under the topic, the effects of refraction of light observed in daily life. We'll study the following cases:

• A partially submerged stick looks to be twisted near the water's surface.
• An object placed underwater appears to be raised
• A pool of water looks to be shallower than it is.

Next comes the laws of refraction of light, refractive index, and speed of light in air and different mediums. This chapter will study the refraction of light by spherical lenses and various lenses like optical centre, principal axis, principal focus, focal length, etc. There are several rules for obtaining images formed by convex lenses. Different type of image is formed by a convex lens when the object is placed at the following different positions:

• Between C and F
• At the F
• Between F and 2F
• At 2f
• At infinity

We'll learn how to determine the focal length of a convex lens quickly and approximately some of its important uses. Sign conventions for special lenses, lens formula, and magnification are other relevant topics of the chapter. Finally, image formation by a concave lens is studied under the following cases: