Question

Two examples of non-luminous objects are:
(A). Stars, the moon
(B). A burning candle, a glowing bulb
(C). The moon, a spoon
(D). Stars, a spoon

Answer 1

- Hint: Recall the definition of luminous and non-luminous objects and also their properties. Then categorize all the objects given in question as either luminous or non-luminous. Then the option in which both non-luminous objects lie is the correct option.

Complete step-by-step solution -

To understand what are the examples of non-luminous objects, we shall have to first know what does luminous and non-luminous mean.
Luminous objects are those which have their own light and even emit their own light. These are usually the visible objects which means they are responsible for visibility in darkness. Our eyes perceive the light reflecting from various objects that allows us to see them. Examples of these objects are sun, stars, torch and candle.
Non-luminous objects are the objects that do not have their own source of light energy and hence they cannot emit light and are not responsible for vision. These objects can only be visible due to luminous objects. Examples of non-luminous objects are the moon, plants, and spoons. Both these categories fall under visible objects.
Now, since we have understood the definition of luminous and non-luminous objects, we can easily identify them. Hence, moon and spoon are the two examples of non-luminous objects. Moon does not have its own source of light energy; it only reflects the sunlight and hence we cannot see the moon unless we have another source of luminous objects. On the other hand, a spoon which is a manmade object is non-luminous as it has no natural source of light energy similar to the sun or even an artificial source like a battery in a torch. Hence, a spoon is also a non-luminous object.
Thus, the moon and spoon are examples of non-luminous objects.

Note:- Luminous objects have their own source of light energy and non-luminous objects do not have their own source of light energy.
Sun and Stars are the best examples of luminous objects. Moon, Plants, and Spoon are the examples of non-luminous objects.