Question

An electron is accelerated under a potential difference of 182 V. The maximum velocity of electron will be (Charge of electron is $1.6 \times 10^{-19}C $ and its mass is $9.1 \times 10^{-31}kg) $

• A. $5.65 \times 10^6 \, ms^{-1} $
• B. $4 \times 10^6 \, ms^{-1} $
• C. $8 \times 10^6 \, ms^{-1} $
• D. $16 \times 10^{-6} \, ms^{-1} $

Answer 1

The Correct Option is C

$\frac {1}{2}mv^2=eV $
$\, \, \, \, \, \, \, \frac {1}{2} \times 9\times10^{-31}\times v^2=1.6 \times 10^{-19} \times 182 $
$\hspace15mm v^2= \frac {1.6 \times 10^{-19}\times182 \times2}{9.1 \times 10^{-31}} $
$\hspace15mm =64 \times 10^{12} $
$\hspace15mm v=8 \times 10^6ms^{-1} $