Question

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

• 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 = $6m^3$.
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.