In a picture tube of television, electrons are accelerated by thousands of volts via a vacuum towards the screen.
(i) When a TV set were laid on its back, what potential difference, acting over a distance of 15 cm, would be required to balance the downward force of gravity so that an electron would remain stationary?
(ii) Given that the normal TV voltage, would electrons still be capable to move upward towards the screen if laid on its back, against the force of gravity? Could they accelerate? Show computations to support your answer.