Suppose the charge of a proton and an electron differ slightly. One of them is e , the other is e + Δ e . 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 Δ e is of the order of [Given mass of hydrogen m h =   1.67 × 10 – 27   kg ]

Step-by-step solution

The net electrostatic force and gravitational force will be equal since the net force on the system is zero. Thus, F E = F g 1 4 π ε 0   Δ e 2 d 2 = G m 2 d 2 9 × 10 9 Δ e 2 = 6.67 × 10 - 11 × 1.67 × 10 - 27 × 1.67 × 10 - 27 Δ e 2 = 6.67 × 1.67 × 1.67 9 × 10 - 74 Δ e   ≈ 10 - 37