Question

(b) If all the charges of a system are in X-Y plane, is it necessary that the centre of charge be in X-Y plane?

Answer 1

Explanation:

(a) It is to be noted that the charges are of two various kinds. They are negative and positive, which is unlike the similar type mass. For example, let us assumed that there is charge of 2q at the origin and -q at 2 units along the x-axis. The charge in the centre will be at a distance$\frac{-2q}{q } =-2.$  It is clear that the charge’s centre, in this scenario, lies external the charges joined by the line segment.  

(b) In this case, as the z-coordinate is zero, so Σiqizi = 0.  

(c) In this scenario, this might lie outside the cube.