Home
Class 12
PHYSICS
In an electron gun, the electrons are ac...

In an electron gun, the electrons are accelerated by the potential `V`. If the `e` is the charge and `m` is the mass of the electron, then the maximum velocity of these electrons will be

A

(a)`(2eV)/m`

B

(b)`sqrt((2eV)/m)`

C

(c)`sqrt((2m)/(eV))`

D

(d)`V^2/(2 em)`

Text Solution

AI Generated Solution

The correct Answer is:
To find the maximum velocity of electrons in an electron gun accelerated by a potential \( V \), we can follow these steps: ### Step-by-Step Solution: 1. **Understanding the Energy Relation**: The kinetic energy gained by the electrons when they are accelerated through a potential \( V \) is given by: \[ \text{Kinetic Energy} = eV \] where \( e \) is the charge of the electron. 2. **Kinetic Energy Formula**: The kinetic energy of an object can also be expressed in terms of its mass \( m \) and velocity \( v \): \[ \text{Kinetic Energy} = \frac{1}{2} mv^2 \] 3. **Setting the Two Expressions Equal**: Since both expressions represent the kinetic energy of the electrons, we can set them equal to each other: \[ eV = \frac{1}{2} mv^2 \] 4. **Solving for Velocity**: To find the maximum velocity \( v \), we rearrange the equation: \[ mv^2 = 2eV \] Now, divide both sides by \( m \): \[ v^2 = \frac{2eV}{m} \] Taking the square root of both sides gives us: \[ v = \sqrt{\frac{2eV}{m}} \] 5. **Final Expression**: Thus, the maximum velocity \( v \) of the electrons is: \[ v = \sqrt{\frac{2eV}{m}} \]
Promotional Banner

Similar Questions

Explore conceptually related problems

What is the mass (m) of an electron?

Wavelength of an electron is 5Å. Velocity of the electron is

The potential difference between two large parallel plates is varied as v = at, a is a positive constant and t is time. An electron starts from rest at t=0 from the plate which is at lower potential. If the distance between the plates is L, mass of electron m and charge on electron -e then find the velocity of the electron when it reaches the other plate.

An electron is accelerated through a potential difference of 200 volts. If e//m for the electron be 1.6 xx 10^(11) coulomb/kg, the velocity acquired by the electron will be

Mention the charge, mass and e/m ratio for an electron.

Maximum number of electrons in the M shell

Kinetic energy of an electron accelerated in a potential difference of 100 V is

Kinetic energy of an electron accelerated in a potential difference of 100 V is

The charge to mass ratio of electron was found out to be

The charge to mass ratio of electron was found out to be