Question

In a cathode ray tube, if V is the potential difference between the cathode and anode, the speed of the electrons, when they reach the anode is propotional to :
(Assume initial velocity = 0)

• A. $V$
• B. $1/V$
• C. $\sqrt{V}$
• D. $\left(v^2|2em\right)$

Answer 1

The correct option is C $\sqrt{V}$

When the electron in accelerated by the potential difference

Towards the anode then the $k\sqrt{2}$ of electrons is equal to workdone by potemtial on electrons is

$\frac{1}{2}m{v}^2=ev$

$\vartheta =\sqrt{\frac{2ev}{m}}$ $\vartheta \times \sqrt{v}$