Question

Which of the following is an opaque object?
A. Wood
B. Glass
C. Air
D. Vacuum

Answer 1

Hint: Try to understand the concept of opaque objects, transparent objects and translucent objects. Try to apply this concept on the given materials to see which one is true.

Complete step by step answer:
Opaque objects can be defined as an object which does not allow light to pass through it. We cannot look through an opaque object. Light rays do not pass through them but other electromagnetic rays may pass through them.
Transparent material can be defined as an object which allows light to fully pass through them. We can see through a transparent material. Transparent objects are the objects which allows almost all the light rays to pass through them.
Translucent objects do not allow all the light rays to pass through them. It allows some of the light rays to pass but blocks most of them.
In the above question wood is the opaque object because wood does not allow light rays to pass through them. So, if we look through a wood then we will not see anything behind it.
The correct option is (A)

Note: Glass is a transparent object. It allows almost all the light rays to pass through them and we can see what is behind the glass.
Air is also a transparent material. Vacuum is also a transparent material since all the light rays or any other electromagnetic rays pass through vacuum.