Given data
*The given potential difference is V = 2.5 x 10^4 V
*The value of the charge of the electron is q = 1.6 x 10^-19 J
The formula for the energy is gained by the electron is given as
Substitute the known values in the above expression as
Hence, the energy is gained by the electron is U = 4.0 x 10^-15 J