Question

A piece of wood of dimensions 1 m by 2 m by 3 m has mass of 2 kg. What is the density of wood? Would the wood float in water? ($d_{water}$ = 1000 $\frac{kg}{\left(m^3\right)}$)

• A. 0.33, YES
• B. 0.33 x 10^-3,NO
• C. 3,YES
• D. 3 x 10^-3, NO

Answer 1

The correct option is A

0.33, YES

Volume of the wood = 1 m$\times$2 m$\times$3 m = 6$m^3$.
So, the density of wood = $\frac{massofwood}{volumeofwood}$.
Hence, $d_{wood}$ = $\frac{2kg}{6m^3}$ = 0.33 $\frac{kg}{m^3}$.
Now, to check whether the wood floats or not we need to calculate the relative density with respect to water as a reference material (or specific gravity).
So, specific gravity = $\frac{0.33}{1000}$ = 0.33 $\times$ ${10}^{-3}$, which is less than 1.
Hence, the substance is less dense than water and it would float.