Sources of Light
Key Concepts
- Sources of light
- Luminous and non-luminous (Illuminated) objects.
Introduction
We see this beautiful world around us using our eyes. However, it is not just the eyes that help us see objects around us. In fact, light is an important thing needed to see objects. This is because we cannot see when it is dark even if we have our eyes open. Some objects give off light and the others do not. In this session, we will group objects into these categories and understand each category well.
We see this beautiful world around us using our eyes. However, it is not just the eyes that help us see objects around us. In fact, light is an important thing needed to see objects. This is because we cannot see when it is dark even if we have our eyes open. Some objects give off light and the others do not. In this session, we will group objects into these categories and understand each category well.
Explanation:
Sources of light:
The objects that give off light are called the sources of light. In the picture below, the Sun is the source of light.
In the picture below, the moon and the stars are the sources of light.
Some animals also emit light such as fireflies, lantern fish, flashlight fish, etc.
Luminous and non-luminous (illuminated) objects:
The objects which emit light of their own are called luminous objects.
The objects which do not emit light of their own are called non-luminous or illuminated objects.
Questions and Answers:
- Identify the objects which are luminous and non-luminous (illuminated) and tick and cross on the boxes accordingly.
Answer:
Summary
- The objects that give off light are called the sources of light.
- The objects which emit light of their own are called luminous objects.
- The objects which don’t emit light of their own
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