Question

A substance through which light can’t pass is called a/ an:
A.) Optical medium
B.) Transparent body
C.) Opaque body
D.) Translucent body

Answer 1

Hint: When light is made incident on a material, three situations can happen. All light will pass through the material, some part of the light passes through the material while rest is reflected or no light passes through the material.

Complete step-by-step answer:
We can classify the materials on the basis of the fact that whether light can pass through them or is reflected from it. There are three categories of objects:

1) Transparent body: A transparent body allows the entire light incident on it to pass through it. One can see clearly to the other side of a transparent object. For example: clear glass, water, etc.

2) Translucent body: A translucent body allows only part of light to pass through it while rest is reflected from it. One cannot see clearly through a translucent object. For example: butter paper, ground glass, etc.

3) Opaque body: An opaque body does not allow any amount of light to pass through it and all light is reflected. One cannot see beyond an opaque object. For example: brick wall, wooden door, etc.

Therefore, the correct answer to the question is option C.

Optical medium is one through which light can travel freely by reflecting from the inner walls of the medium. The reflecting walls are opaque while the medium is transparent.

Note: We can see an object in front of us because it reflects the light incident on it. The colour of the object is because of the fact that it reflects certain light while absorbing the other. The phenomenon of reflection makes things visible.