A passenger car acquires a net static charge of +5 mC relative to Earth during a long…
PHYSICS · Multi-part · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
A passenger car acquires a net static charge of +5 mC relative to Earth during a long drive in very dry weather. When the car stops, an engineer attaches a flexible conducting strap that touches the ground, forming a direct electrical connection between the metal body of the car and Earth. After several seconds the strap is removed.
(a) Explain what happens to the electric potential of the car body while the strap is attached.
(b) Describe the direction of electron flow (to Earth or to the car) during the grounding process and justify your answer.
(c) After the strap is removed, the car and Earth are no longer in contact. Discuss whether the car retains any net charge and whether its electric potential differs from that of Earth. Provide reasoning to support your conclusions.