Question

Three electric charges are located as shown in the diagram, with q-7.8.uC, q7.8.uC, q8.7.pC, a b = 0.62-m, and c 0.77-m. What is the electric force on charge q due to charges qi and q? 0.38 m, 2. magnitude a. 0.805.N b. 0.7425.N C. 1.207 N d. 0.9494 N e 0.7474.N f. 1.061 N 3. direction (as rotation angle) a. 10.73 b. 12.13 c. 16.08 d. 23.76 e. 8.538 13.97 q1 a 42

Answer 1

Like charges attracts and unlike charges repels ,so identify the direction of forces

First Find Forces F_a and F_b

q = -7.8*10^-6 C

q₁ = -7.8*10^-6 C

q₂ = 8.7*10^-6 C

By Coulomb's Law

where k is 8.99*10⁹

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Now split these forces into its Sine and Cosine components

Consider all Forces in x direction

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Consider all Forces in y direction

$F_{y}=0.1782N$

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Resultant Force $F=\sqrt{F_{x}^{2}+F_{y}^{2}}$

$F=\sqrt{0.7174^{2}+0.1782^{2}}$

$F=0.7392N$

ANSWER: Option b. 0.7425N

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Direction

tano -F/FI

$tan\theta = 0.1782/0.7174$

$\theta =13.948^{\circ}$

ANSWER: Option f. 13.97 deg

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