Physics

Problem

85. A point charge

+q

is placed midway between two point charges

+3 q

and

-q

separated by a distance

2 d

. If Coulomb's constant is k , the magnitude of the force on the charge +q is: (A)

2 \frac{k q^{2}}{d^{2}}

(B)

4 \frac{k q^{2}}{d^{2}}

(C)

6 \frac{k q^{2}}{d^{2}}

(D)

8 \frac{k q^{2}}{d^{2}}

(A)

2 \frac{k q^{2}}{d^{2}}

(B)

4 \frac{k q^{2}}{d^{2}}

(C)

6 \frac{k q^{2}}{d^{2}}

(D)

8 \frac{k q^{2}}{d^{2}}