An electron of charge 1.6 x 10-19C is accelerated between two metal plates. If the kinetics energy of the electron is 4.8 x 10-17J, the potential difference between the plate is
-
A.
30V -
B.
40V -
C.
300V -
D.
400V
Correct Answer: Option C
Explanation
In general, if a charged particle is accelerated between two metal plates/a region by potential difference V volts, the work done on the charge, given by the product of the charge and the potential difference, is equal to the kinetic energy of the charge
Thus eV = K.E
1.6 x 10-19 x V = 4.8 x 10-17
| ∴ V = | 4.8 x 10-17 |
| 1.6 x 10-19 |
= 300V