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JEE · NEET Previous Year Question

$The twinkling effect of star light is due to$

Topic: JEE PYQ

Answer: D. Full step-by-step solution below.

A $total internal reflection$
B $high dense matter of star$
C $constant burning of hydrogen in the star$
D $the fluctuating apparent position of the star being slightly different from the actual position of the star.$

Correct answer: D

Solution

(c): When energy is produced by fusion and fission, the vapours flictuate and move towards less dense places outwards. Convection causes twinkling.

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