Question

The volume of 50 g of a substance is $20c{m}^3$. If the density of water is $1gc{m}^{-3}$, will the substance float or sink? [3 Marks]

Answer 1

Density of the substance $=\frac{\text{Mass of the substance}}{\text{Volume of the substance}}=\frac{50}{20}gc{m}^{-3}$
$=2.5gc{m}^{-3}$
Density of water $=1gc{m}^{-3}$ [2 Marks]

If the density of an object is more than the density of a liquid, then it sinks in the liquid, otherwise, it floats.
Here the density of the substance is more than the density of water, so it will sink in water. [1 Mark]