A fricionless wire AB is fixed on a sphere of radius R. A very small particle slips on the wire. The journey from A to B is performed in time
time taken by this ball to slip from A to B is:
AB = R/(cos Ө) theta = 45o
AB = √2 R = 2R/√2 = 2R cosѲ
2R cosѲ = 1/2x gcosѲ x t2
t = 2 √R/g