A point charge is fixed at the origin

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

Problem

A point charge

Q=+6.0\,\mu\text{C}

is fixed at the origin. A

+1.0\,\mu\text{C}

test charge will be moved from point

A

(0.080\,\text{m},\,0)

to point

B

(0,\,0.080\,\text{m})

. (a) Calculate the electric potential at points

A

and

B

due to the fixed charge

Q

. Express your answers in volts. (b) Determine the work that must be done by an external agent to move the test charge directly from

A

B

along the straight-line segment connecting the two points. (c) A student suggests moving the test charge first along the

x

-axis from

A

to point

C

(0.080\,\text{m},\,0.080\,\text{m})

, then along the

y

-axis from

C

B

. For each leg of this two-step path, calculate the work done by the external agent and show that the total work equals the result from part (b). (d) Using your results, explain what this comparison reveals about the nature of the electric force field produced by point charge

Q

Related theory

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