I found an answer from descanso.jpl.nasa.gov

Fundamentals of Electric Propulsion: Ion and Hall Thrusters

and **specific** impulse is somewhat less than that achievable in ion thrusters, but
the thrust ... **electrons emitted** from the hollow cathode also leave the thruster with
the ion ... is equal to the mass of the spacecraft, **M**, times **its** change in **velocity**, **v**:
... **electrons** between two plasmas **or** between a plasma and an **electron emitter**.

For more information, see Fundamentals of Electric Propulsion: Ion and Hall Thrusters

I found an answer from www.jagranjosh.com

CBSE **Class 12th Physics** Notes: **Dual Nature** of **Radiation** and **Matter**

Jan 19, 2017 **...** CBSE **class 12** chapter wise notes based on chapter 11, **Dual Nature** of
**Radiation** and **Matter**, of **class 12 NCERT Physics** textbook are available in ...
**Photoelectric Effect** and **Wave Theory** of **Light**. **Photon**. **Einstein's Photoelectric**
**Equation**: **Energy Quantum** of **Radiation** ... **Kinetic Energy** of Photoelectron.

For more information, see CBSE **Class 12th Physics** Notes: **Dual Nature** of **Radiation** and **Matter**

Given that

Potential difference V =. 500 V

Specific charge of electron \frac{e}{m} = 1.76*10^{11} C/kg

a)

Step 1: Get an expression for emitted electron speed

Required formulas

Kinetic energy K.E=\frac{1}{2}mv^2 .............................(1)

Where, m - mass and v - velocity

According to the conversion law

K.E = eV .............................(2)

Where, charge of electron e=1.6*10^{-19} and V - potential difference(voltage)

From equation (1) and (2)

\frac{1}{2} mv^2 = eV

v = \sqrt{\frac{2eV}{m}}

v = \sqrt{2 V \frac{e}{m}} .............................(3)

Step 2: Finding the speed of emitted electron

Plug in the given values in equation (3)

v = \sqrt{ 2 * 500 * 1.76*10^{11} }

v = 1.327* 10^7 m/s

b)

Collector potential V = 10 M V = 10* 10^{6} V

Step 1: Speed of emitted electron form collector

Speed v = \sqrt{2 V \frac{e}{m}}

v = \sqrt{2*10^7 * 1.76*10^{11}}

v = 1.88 * 10^{9} m/s

Step 2: Observation

Speed of light c = 3* 10^{8} m/s [/math]

Speed of light less the speed of electron ( v > c) which is not possible practically since noting can travel faster than

speed of light.

The relativistic mass is given as follows

Modified mass m=m_0*(1-\frac{v^2}{c^2})^{-\frac{1}{2}}

m_o - mass of particle at rest position