Question

Two large parallel plates each have an area of 250 cm^2 . When the two plates are separated by air, the system has a capacitance of 2.1 nF . The first plate has a charge of +20 nC and the second plate has a charge of −20 nC .

(a) What is the separation between the two plates?

(b) What is the potential difference between the two plates? Which plate has a larger potential?

(c) What is the magnitude and direction of the electric field between the two plates?

(d) If an electron is released from rest in the middle of the gap, which way will it move? (Note: The charge of an electron is −1.6 x 10−19 C)

(e) If an electron is released from rest in the middle of the gap, what speed will it have when it hits one of the plates? (Note: The mass of an electron is

9.11 x 10−31 kg )

Answer 1