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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.
13
No external torque I1 1 = I2 2, with I = 25MR2, = 2 T
T R2
T2 = 24 ( 34 )2 = 24 916 = 13.5 h
= 13 hours 30 minutes
Answer: 13
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