Question

A boy wants to determine the density of an irregularly shaped stone. First he finds the mass of the stone to be 100 g, next he lowers the stone in to a measuring cylinder containing water as shown.The density of the stone is(A) 2500 kg m3 (B) 400 kgm–3 (C) 4 kgm–3 (D) 2.5 kgm–3

Answer 1

Answer is B.

The volume of the stone is equal to the volume of the water increased in the measuring cylinder.

The volume of the stone is calculated from the formula Volume =Mass/Density.

In this case, the Mass = 12 g and Density = 3gcm

3

.

Volume = 12/3 = 4cm

3

.

The actual volume of liquid in the measuring cylinder is 20cm

3

.

So, the increase in volume will show a new reading of 20cm

3

+4cm

3

=24cm

3

.