If the angular velocity of earth's spin is increased such that the bodies at the equator start floating, the duration of the day would be approximately : [Take g = 10 ms$-$2, the radius of earth, R = 6400 $\times$ 103 m, Take $\pi$ = 3.14]
Solution
For objects to float<br><br>mg = 2$\omega$<sup>2</sup>R<br><br>$\omega$ = angular velocity of earth.<br><br>R = Radius of earth<br><br>$\omega = \sqrt {{g \over R}}$ ..... (1)<br><br>Duration of day = T<br><br>$T = {{2\pi } \over \omega }$ ..... (2)<br><br>$\Rightarrow T = 2\pi \sqrt {{R \over g}}$<br><br>$= 2\pi \sqrt {{{6400 \times {{10}^3}} \over {10}}}$<br><br>$\Rightarrow {T \over {60}}$ = 83.775 minutes<br><br>$\simeq$ 84 minuites
About this question
Subject: Physics · Chapter: Gravitation · Topic: Kepler's Laws
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