Chapter 9: Light Reflection and Refraction

Introduction

• Light is a form of energy.
• Light enables us to see objects from which it comes or from which it is reflected.
• Objects like the sun, bulb, fire etc. which emit their own light are called luminous objects.
• Objects which do not emit their own light are called non-luminous objects.
• Light travels in a straight line.
• Light has wave as well as particle nature.
• It does not need a material medium to travel that is light waves can travel in a vacuum also.
• The speed of light is 3,00,000 kilometres per second.
• The speed of light is different in different transparent media.