Question 13 Marks
A rectangular piece of wood measures $4 \ cm$ by $6 \ cm$ by $8 \ cm$ and has a mass of $20 g.$ What is the density of the piece of wood ?
Answer
View full question & answer→Volume of the piece of wood $=(4 \times 6 \times 8) \ cm ^3=192 \ cm ^3$
Mass of the piece $=20 g$
Density $=\frac{\text { Mass }}{\text { Volume }}$
$\frac{20 g }{192 \ cm ^3}=0,104 g \ cm ^{-3}$
Relative density of wood
$=\frac{\text { Density of wood }}{\text { Density of water at } 4^{\circ} C }$
$=\frac{0.104 g / \ cm ^3}{1 g / \ cm ^3}$
$=0.104$
Mass of the piece $=20 g$
Density $=\frac{\text { Mass }}{\text { Volume }}$
$\frac{20 g }{192 \ cm ^3}=0,104 g \ cm ^{-3}$
Relative density of wood
$=\frac{\text { Density of wood }}{\text { Density of water at } 4^{\circ} C }$
$=\frac{0.104 g / \ cm ^3}{1 g / \ cm ^3}$
$=0.104$