For objects to float,
mg=mω2R
ω= angular velocity of the earth.
R= Radius of earth
ω=Rg...(1)
Duration of day =T
T=ω2π...(2)
⇒T=2πgR
=2π106400×103
⇒60T=83.775 minutes
≃84 minutes
JEE Main 2021 — Physics Mechanics
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=10ms−2, the radius of earth, R=6400×103m, Take π=3.14)
Held on 18 Mar 2021 · Verified 6 Jul 2026.
60 minutes
does not change
1200 minutes
84 minutes
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