Physics
Grade-10
Easy
Question
When the incandescent bulbs are seen through a turbulent stream of hot air rising above a fire, they appear to be flickering. Why?
- The refractive index of the air above the fire is not stationary
- The temperature of the air above the fire is not stationary
- The physical conditions of the air above the fire are not stationary
- All of the above
Hint:
Light coming from such places travel through a medium of changing refractive index
The correct answer is: All of the above
Space above the fire is hot and its density and hence refractive index changes frequently. Light coming from such places travel through a medium of changing refractive index therefore apparent image of the object also appears changing or flickering.
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