Question

A point charge is located at q1=μc,(2m,1m) and a charge is located at q2= -5μc(-2m,4m) find the force exerted by q1 on q2

Answer 1

Explanation:

Let position vector of q1 is r1 and position vector of q2 is r2

e.g., r1= (-1, 1, 1) and r2 = (3, 1, -2) magnitude of r = lrl = √{4² + 0² + (-3)²) = 5 = 9 × 10^9 x 20 × 10^-12

we have to find magnitude and unit vector along force on q2.

so, position vector of q2 with respect to q1, r = r2- r1=(3, 1, -2) - (-1, 1, 1) = (4, 0, -3)

magnitude of force on q2 = kq1q2/lr|²

= 9 × 10^9 x 20 x 10^-6 x 25 x 10^-6 /5²

= 0.18 N

now, unit vector along force on q2 = (r2 - r1)/Ir2 r1l = (4, 0, -3)/5 = (0.8, 0, -0.6)

hence, unit vector is (0.8, 0, -0.6).