1.An electron leaves the negative terminal of a cathode ray tube and travels towards the
positive plate starting from rest. The electric potential difference between the plates is 2x104
Volts. [mass of electron = 9.11x10-31 kg and the charge on an electron is 1.6x10-19C]
a. Draw a diagram.
b. Calculate the electron’s kinetic energy when it reaches the positive plate.
c. Calculate the electron’s velocity when it reaches the positive plate.
2. When a proton is moved against an electric field by an unbalanced force, what happens to
the change in electric potential energy? Is it positive or negative? Explain using a diagram
and the concept of work
3. An electron is travelling horizontally at a speed of 1.5x106 m/s through two horizontal
plates. It starts at the negative plate at the top. The plates are 10cm long and the electric
field strength between the plates is 100N/C. Calculate the final velocity of the electron as it
leaves the plates
4. At a certain point P in an electric field, the magnitude of the electric field is 12 N/C.
Calculate the magnitude of the electric force that would be exerted on a point charge of 2.5 x
10-7 C, located at P