Due to the rotation of the earth,
Changed gravitational acceleration, g′=g−ω2Rcos2θ
At the equator, angle of inclination, θ=0
43g=g−ω2R
w2R=4g
w=4Rg
=4×6400×10310
=2×8×1001
=16001=161×10−2=0.6×10−3rads−1.
JEE Main 2017 — Physics Mechanics
If the Earth has no rotational motion, the weight of a person on the equator is W. Determine the speed with which the earth would have to rotate about its axis so that the person at the equator will weigh 43W. The radius of the Earth is 6400km and g=10ms−2
Held on 8 Apr 2017 · Verified 6 Jul 2026.
0.63×10−3rads−1
0.28×10−3rads−1
1.1×10−3rads−1
0.83×10−3rads−1
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