Question

Five point masses m each are place at five comers of a regular pentagon. Distance of and corner from centre is r. Match the following two columns.

Column I	Column II
(a) Gravitational field strength at centre	(p) Gm/r2
(b) Gravitational potential at centre	(q) 4Gm/r
(c) When one mass is removed gravitational field strength at centre	(r) zero
(d) When one mass is removed gravitational potential at centre	(s) None of these

Answer 1

Correct option (a) → r, (b) → s, (c) → q, (d) → s

Explanation :

Gravitational field at centre is zero, a → r. Gravitational potential at centre = 5Gm/r = b → s