Question

A charged cloud system produces an electric field in the air near the earths surface.A particle of charge $-2\times {10}^{-9}C$ is acted on by a downward electrostatic force $3\times {10}^{-6}N$ of when placed in the field,The gravitational and electrostatic force,Respectively,exerted on a proton placed in this field are

• A. $1.64\times 10^{-26}N,2.4\times 10^{-16}N$
• B. $1.64\times 10^{-26}N,1.5\times 10^{3}N$
• C. $1.56\times 10^{-18}N,2.4\times 10^{-16}N$
• D. $1.5\times 10^{3}N,2.5\times 10^{-16}N$

Answer 1

The correct option is D $1.5\times 10^{3}N,2.5\times 10^{-16}N$

$qE=3\times {10}^{-6}N2\times {10}^{-9}=3\times {10}^{-6}E=\frac{3\times {10}^{-6}}{2\times {10}^{-9}}=1.5\times {10}^3$

Electrostatic force $=qE=1.67\times {10}^{-19}\times 1.5\times {10}^3=2.505\times {10}^{-16}N$