Comparison Note — Conductor vs Insulating Sphere (Charged) — Notes | NoteTube

Property	Conducting Sphere (charge Q, radius R)	Insulating Sphere (charge Q uniformly distributed, radius R)
Charge location	Only on surface	Throughout volume (uniform)
E at r > R	kQ/ $r^{2}$ (same as point charge)	kQ/ $r^{2}$ (same as point charge)
E at r = R	kQ/ $R^{2}$	kQ/ $R^{2}$
E at r < R	0 (conductor property)	kQr/ $R^{3}$ (linear in r)
E at center (r=0)	0	0
Graph shape (E vs r)	0 inside, peak at surface, falls as 1/ $r^{2}$	Rises linearly to surface, falls as 1/ $r^{2}$ outside
NEET trap	Students think E=0 anywhere inside any sphere	Students forget E≠0 inside insulator