Question

1. A cathode Ray tube is operated at 2,500V. What is the speed of electrons emitted?

Answer 1

Dear student,
​​​​​here
The energy gained by each electron is 2500 eV or (2500 X 1.6X10^-19=4 × 10ˉ¹⁶ J).
Using the kinetic-energy equation, E = ½mv², we get
v = √(2E/m) = 2.96 × 10⁷ m/s, or about 10% of the speed of light.
​​​​​so the speed of electron emitted is 2.96 × 10⁷ m/s.
regards.