Question

The electric field that can balance a charged particle of mass $3.2 \times 10^{-27}\, kg$ is (Given that the charge on the particle is $1.6 \times 10^{-19}\, C$)

• A. $19.6 \times 10^{-8}\, N\,C^{-1}$
• B. $20 \times 10^{-6}\, N\,C^{-1}$
• C. $19.6 \times 10^{8}\, N\,C^{-1}$
• D. $20 \times 10^{6}\, N\,C^{-1}$

Answer 1

Answer: (A)

Here, $m = 3.2 \times 10^{-27}\, kg$, $e = 1.6 \times 10^{-19} \,C$, $g=9.8\,m \,s^{-2}$
As $E=\frac{F}{q}=\frac{mg}{e}$
$=\frac{3.2\times10^{-27}\times9.8}{1.6\times10^{-19}}$
$=19.6\times10^{-8}\,N\,C^{-1}$