PHYSICS · Multi-part · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
Consider a pair of parallel plates, separated by a distance of 4.0 cm, across which there is a potential difference of 12 V. A charged particle of charge 4 mC, and mass 1.5×10−3 kg, is placed immediately next to one of the plates so that the electric field between the plates will accelerate the point charge towards the other plate.
(a) i Calculate the electric field strength between the two plates. ii Hence, determine the acceleration of the charged particle. iii Hence, determine the time it will take for the charged particle to reach the other plate. iv Hence, determine the speed of the charged particle just before it hits the other plate. v Hence, determine the kinetic energy of the charged particle just before it hits the other plate.
(b) i How much work will the electric field do on the charged particle in moving it from one plate to the other? ii Compare and comment on your answer to parts a v and b i.