Final speed of an accelerated electron

[gidra]

Whit is the final speed of an electron accelerated through a potential difference of 200 V if has an initial speed of 2.0 x 10^6 m/s. (Charge of electron = 1.6 x 10^-19 C and mas of electron = 9.11 x 10^-31 kg)

 

[Dick]

I don't know. What's the definition of 'potential difference', i.e. V. How much energy does it gain? How much energy did it start out with? Can you convert that back into speed?