Question

Deuteron and alpha particle in air are at separation $1\,?$ The magnitude of electric field intensity on $\alpha$-particle due to deuteron is

• A. $5.76 \times 10^{11} N / C$
• B. $1.44 \times 10^{11} N / C$
• C. $2.828 \times 10^{11} N / C$
• D. zero

Answer 1

Answer: (B)

$1.44 \times 10^{11} N / C$

Answer 2

The intensity of electric field $(\vec{E})$ due to charge $q$, is given by

$E=\frac{1}{4 \pi \varepsilon_{0}} \frac{q}{r^{2}}$
Given, $r=1\,?=1 \times 10^{-10} m$,
$q =1.6 \times 10^{-19} C$
$\therefore E =9 \times 10^{9} \times \frac{1.6 \times 10^{-19}}{\left(1 \times 10^{-10}\right)^{2}}$
$=1.44 \times 10^{11} N / C$