A small sphere is charged uniformly and placed at point A (u, v) so that at point B (8, 7) electric field strength is` vecE = (54 hati + 72hatj)` N/C and potential is+ 900V. Calculate:
(a) Magnitude of charge,
(b) Co-ordinates of point A, and
(c ) If di-electric strength ofair is `3 xx I0^(6)` V/m, minimum possible radius of the sphere.

Answer

[(a)`1muC`;(b)(2,-1);(c)`sqrt(3xx10^(-3))`m or 5.48cm]