Along the –axis inside a certain device

PHYSICS · Multi-part · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

Along the

x

–axis inside a certain device, the electric potential (in volts) is given by the analytic expression

V(x)=8.0-4.0x

where

x

is in centimeters. A proton is placed at

x=0.50\,\text{cm}

. (a) Calculate the magnitude of the electric field at

x=0.50\,\text{cm}

. Include appropriate units. (b) Indicate the direction of the electric field at that position along the

x

–axis and explain your reasoning. (c) Determine the average electric field magnitude between

x=0.50\,\text{cm}

and

x=1.50\,\text{cm}

, and compare this result with the instantaneous value found in part (a). Comment on any difference or similarity.