Question

The apparent position of an object, when seen through the hot air, fluctuates or wavers. State the basic cause of this observation.

Answer 1

Refraction of light:

1. Refraction of light happens when a ray of light travels at some angle into a different medium with a different refractive index.
2. It generally takes place when the intensity of a refracted ray of light is less than an incident ray. Hence ray of light is refracted when the variation of some of the light takes place.
3. Incident ray, refracted ray, and normal at the point of incidence, will all lie in the same plane of the axis.
4. The ratio between the sine of the angle of incidence to the sine of the angle of refraction is constant throughout both of the given mediums.

Cause of fluctuation of light:

1. When we see the apparent position of an object through the hot air, it fluctuates or wavers.
2. The main reason of this phenomenon is the refraction of light through variation in the physical condition of hot air.
3. If we see any object through the hot air over a fire, the object looks to be trembling slightly due to the refraction of light.
4. When the air above the fire receives some heat, it becomes less dense, but the colder air, which goes further up is denser.
5. Hence, when we look at some objects by the light coming from them through hot and cold air layers having different densities, the refraction of light takes place, due to which the objects appear to be shaking slightly.

Thus, the position of an object, when we see through the hot air, fluctuates due to the refraction of light.