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Back to Coulomb's Law — Problem 3 · 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
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Fluency Practice

Use k=9×109k = 9 \times 10^9 N·m²/C². Show your work and state the direction of each force.

1.

Calculate the magnitude of the electric force between q1=+2×10−6q_1 = +2 \times 10^{-6} C and q2=−4×10−6q_2 = -4 \times 10^{-6} C separated by r=0.20r = 0.20 m. Express your answer in newtons to two significant figures.