Rotational MotionHard
Question
If the earth were to suddenly contract to 
th of its present radius without any change in its mass then the duration of the new day will be nearly : -
th of its present radius without any change in its mass then the duration of the new day will be nearly : -Options
A.
hour
hourB.24n hour
C.
hour
hourD.24n2 hour
Solution
There is no exertial torque so the angular momentum remains constant as due to contraction the MI of earth decreases.
I2 =
Now I1ω1 = I2ω2 =
∴ T2 =
⇒ T2 = 
∴ T2 = 
I2 =
Now I1ω1 = I2ω2 =
∴ T2 =
⇒ T2 = ∴ T2 = Create a free account to view solution
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