How do we see things around us? Ever wondered?
If you go inside a room with no light at night. You cannot see anything in it unless you light a candle or a torch. Light helps us to see our surroundings.
Many objects give out their own light. Electric lights, candles, bulbs, and even the sun in the sky are “luminous” objects.
When light from luminous objects falls on other objects, it travels to our eyes and helps us see these objects as they are.
The objects on which light falls can also be categorised into transparent, translucent, and opaque.
Look at these objects and experiment with them.
Transparent objects: are objects that light can fully pass through to the other side. We can see the other side clearly through glass, spectacles, and lenses.
Translucent objects: If we can see the other side of the object though not very clearly, the object is translucent. This is because only some light can pass through the object to the other side. Tracing paper is the most common example of a translucent object.
Opaque objects: If light cannot pass through the object at all, we cannot see the other side at all. Some examples are chairs, pens, shoes, etc.
Light forms a black image of the opaque object on the other side. This black image is the “shadow” of that object.
This way we can identify the object just by looking at the shadow.
However, we can see the shadow only if the shadow falls on a surface like a wall, cardboard, or floor but not if the source of light points to the sky
Have you ever tried making different shadows with your hands on?
Did you see the colour of your hand on the wall? A shadow cannot show colour either. The shadow of a red rose, a yellow banana, and even a white rabbit would be black.
The size of the shadow changes depending on how far the object is from the surface of the shadow. If the object is far away, the shadow would be big. But if it is close to the surface, the shadow would be small.
A camera uses light to capture images. If you want to make a camera, it is very easy.
Just take two boxes where one is slightly bigger than the other.
Cut open one side of the box.
Make a tiny hole on the opposite side of the cut side of the bigger box.
Make a small square of 2-3 inches on the smaller box and cover it using tracing paper.
Place this box with the square in the same direction behind the pin-hole on the bigger box.
The Pin-hole camera is now ready for use.
This pinhole camera can be used to view near and far objects. However, the images appear upside-down. You can even use this camera to see the sun. Avoid looking directly at the sun to protect your eyes.
We all use mirrors at home. Do you know how you can see your image in the mirror?
Light travels in a straight line. Mirrors are special opaque objects. They return light in the same direction that it came from. This makes us see the image of the object in front of the mirror. It is called reflection.
And just like that, you have finished online revisions of the chapter- Light, Shadow, and Reflection from your Class 6 NCERT Science textbook. Did you find it interesting? You can find more interesting stuff to read and learn at SeekoG. On this online learning platform, you could do quick revisions within a few minutes and master a lesson in no time using online mind maps. You can also check your mastery over the topics through SeekoG Academic Diagnostic Tests and get an in-depth analysis of your performance through SeekoG Gap Analysis Reports. SeekoG 1:1 Tuitions are available where you can find the best tutors online to help strengthen the areas of the chapter in which you need improvement. These online MCQ tests also help you to prepare for various competitive exams and Olympiads in school as well as help you in CBSE board exam preparation.