Question

Electrons are accelerated by voltage $V_0,$ initially electrons were at rest, speed after covering distance x is

• A. $v\propto V_0$
• B. $v\propto \sqrt{x}$
• C. $v\propto \sqrt{V_0}$
• D. $v\propto x$

Answer 1

The correct option is C $v\propto \sqrt{V_0}$

Potential energy of point charge = qV
(q - charge, V = potential)
$qV+0=q{V}^{\prime }+\frac{1}{2}m{v}^2$
$\frac{1}{2}m{v}^2=q(V-V^{\prime })=q{V}_0$
$v\propto \sqrt{V_0}$