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JEE Main20246 Apr 2024Morning ShiftPhysicsRotational MotionActual

If the radius of earth is reduced to three-fourth of its present value without change in its mass then value of duration of the day of earth will be ______ hours 30 minutes.

Correct answer

0

Step-by-step solution

By conservation of angular momentum aligned & I ₁ ₁= I ₂ ₂ & ( 2 5 MR ^2 ) 2 T ₁ = 2 5 M ( 3 4 R )^2 2 T ₂ & 1 ~T ₁ = 9 16 ~T ₂ & 1 ~T ₂ = 9 16 T ₁= 9 16 24 hr = 27 2 hr =13 hr 30 mins . aligned

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