Back to Coulomb's Law — Problem 5 · Task Set 4

Exercises: Coulomb's Law

Work through each section in order. Use $k = 9 \times 10^9$ N·m²/C² throughout. Show your work on all calculation problems.

Grade 11·20 problems·~35 min·OpenStax Physics (High School)·section·sec-18-2

Work through problems with immediate feedback

Fluency Practice

Use $k = 9 \times 10^9$ N·m²/C². Show your work and state the direction of each force.

A number line showing three charges: A (+4 μC) at 0 m, B (−2 μC) at 0.30 m, and C (+3 μC) at 0.50 m

Three charges are on a line. Charge A ( $+4 \mu$ C) is at position 0, charge B ( $-2 \mu$ C) is at 0.30 m, and charge C ( $+3 \mu$ C) is at 0.50 m. Find the net force on charge B.

Taking rightward as positive, what is the net force on B in newtons? (Positive = right, negative = left.) Express your answer to two significant figures.