If the earth suddenly contracts to one third of its present size, calculate by how much would the day be shortened ?

If the earth suddenly contracts to one third of its present size, calc

1.	If the earth suddenly contracts to one third of its present size, calculate by how much would the day be shortened ?
Answer» Here, `R_(2) = (1)/(3)R_(1), T_(1) = 24 hrs, T_(2) = ?` According to the principle of conservation of angular momentum `I_(2)omega_(2) = I_(1)omega_(1)` `I_(2) ((2pi)/(T_(2))) = I_(1) ((2pi)/(T_(1)))` `T_(2) = (I_(2))/(I_(1)) xx T_(1) = ((2)/(5)MR_(2)^(2))/((2)/(5)MR_(1)^(2)) xx T_(1)` `T_(2) = T_(1) xx ((R_(2))/(R_(1)))^(2)` `= 24 xx ((1)/(3))^(2) = 2 hr 40 min`. `:. T_(1) - T_(2) = 24 hr - 2hr 40 min` `= 21 hr 20 min`

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If the earth suddenly contracts to one third of its present size, calculate by how much would the day be shortened ?

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