Question

A beaker of mass 50 g, with 262 g of water in it, is kept on a weighing machine. A uniform hollow brass ball of total volume 36π cc is inserted into the water in the beaker. It is observed that the ball floats on water. The weighing machine now reads 400 g. Density of brass is 8 g/cc, while that of the inside the brass ball can be neglected. Thickness of the brass used to prepare the ball must be nearest to _______ .

(a) 0.5 mm 

(b) 0.8 mm 

(c) 1 mm

(d) 1.2 mm

Answer 1

Correct option: (c) 1 mm

Explanation:

So thickness = R – r = 3 – 2.899 = 3 – 2.9 = 0.1 cm = 1 mm.