The net electrostatic force and gravitational force will be equal since the net force on the system is zero. Thus, FE=Fg
4πϵ01d2Δe2=d2Gm2
9×109(Δe2)=6.67×10−11×1.67×10−27×1.67×10−27
Δe2=96.67×1.67×1.67×10−74
Δe≈10−37
NEET UG 2017 — Physics Electromagnetism
Suppose the charge of a proton and an electron differ slightly. One of them is e, the other is (e+Δe). If the net electrostatic force and gravitational force between two hydrogen atoms placed at a distance d (much greater than atomic size) apart is zero, then Δe is of the order of [Given mass of hydrogen mh=1.67×10–27kg]
Held on 30 Apr 2017 · Verified 9 Jul 2026.
10−20C
10−23C
10−37C
10−47C
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