Physics 2008 JAMB Past Questions - Question 35: An object placed at the bottom of well full of clear water appears closer to the surface due to

Correct Answer

C

Explanation

Real depth and apparent dept is due to refraction lightWhen an object is placed at the bottom of a well full of clear water, it can appear closer to the surface due to the phenomenon of refraction. Refraction is the bending of light as it passes from one medium (in this case, air) into another medium with a different optical density (water in the well). This bending of light can create optical illusions and cause objects to appear differently than they actually are.

Here's how it works:

1. Light travels at different speeds in different mediums. It travels slower in water than in air.

2. When light from the object at the bottom of the well enters the water surface, it slows down and bends towards the normal line (an imaginary line perpendicular to the surface). This bending is what we call refraction.

3. As the light continues to pass through the water, it bends again when it exits the water and enters the air.

4. Because the light rays have bent as they pass from water to air, they follow a different path than if there were no refraction. The observer at the top of the well sees the object in a position where the light rays appear to come from, which is slightly offset from the actual position of the object.

The net effect of this bending of light is that the object appears to be closer to the water's surface than it actually is. This is why, when you look into a well or a swimming pool, for example, objects at the bottom can seem nearer to the surface than they really are due to the refraction of light at the water-air interface.