Question

The force between two electrons when placedair is equal to 0.5 times the weight of an electrons find the distance between two electrons (masselectron $=9.1\times {10}^{-31}kg)$

• A. 7.2$m$
• B. 72$cm$
• C. 72$m$
• D. 720$m$

Answer 1

The correct option is A 7.2$m$

$0.5\times 9.1\times {10}^{-}31\times 9.8=9\times {10}^9(1.6\times {10}^{-}19)(1.6\times {10}^{-}19)/r^2$

then$,$ solving, $r=7.2m$

Hence,

option $\left(A\right)$ is correct answer.