A physics textbook verbally describes two different electric-field line diagrams,…
PHYSICS · Multi-part · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
A physics textbook verbally describes two different electric-field line diagrams, Diagram 1 and Diagram 2, for single isolated point charges.
• Diagram 1: Eight straight radial lines extend outward symmetrically from a central point.
• Diagram 2: Sixteen straight radial lines converge uniformly toward a central point.
Using only this information, respond to the following prompts.
(a) For each diagram, state whether the central point represents a positive or a negative charge and explain your choice.
(b) Compare the electric-field magnitudes at equal distances from the central point for the two diagrams. Provide a qualitative ranking and justify it using properties of electric-field line density.
(c) Suppose a small positive test charge is released from rest at a location two radii away from the center in each diagram. Compare the initial acceleration vectors of the test charge in Diagram 1 and Diagram 2, explaining any differences.