Question

an electron is accelerated through a potential difference V. Write an expression for its final speed ,if it was initially at rest

Answer 1

I'm writing this answer assuming you know basics of electrostatics.

Work done = e×V (e - charge on electron, V -  potential difference) 

Since this work is stored in the form of Kinetic energy , 
(0.5)mv² = e×V 

Therefore v = [(2×e×V)÷m]^½

Answer 2

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