Question

The p.d. between two plates separated by a distance of $1mm$ is $100V$. The force on an electron placed in between the plates is

• A. ${10}^{5}N$
• B. $1.6\times {10}^{-24}N$
• C. $1.6\times {10}^{-14}N$
• D. $1.6\times {10}^{-19}N$

Answer 1

Answer: (C)

$1.6\times {10}^{-14}N$

Given p. d between plates $=100V$
we know $E=\frac{V}{d}$

$\Rightarrow E=\frac{100}{1\times {10}^{-3}}$

$\Rightarrow E={10}^5$
Force $F=qE$
$={10}^5\times 1\cdot 6\times {10}^{-19}N$
$1\cdot 6\times {10}^{-14}N$