Mass, Weight and Density Questions and Answers - Form 1 Topical Mathematics

Questions

1. A piece of metal has a volume of 20 cm³ and a mass of 300g. Calculate the density of the metal in kg/m³.
2. 2.5 litres of water density 1g/cm³ is added to 8 litres of alcohol density 0.8g/cm³. Calculate the density of the mixture
   

Answers

1. Density = ^{(300 x 1,000,000)}/_{(20 x 1000)}
   =15,000 kg/m³
2. D = ^M/_V
   Mas = D x V
   = 1g/cm³ x 2500cm³
   = 2500g..........................................(i)
   Mass = 0.8 x 8000
   = 6400g .....................................(ii)
   total mass = (2500 + 6400)g
   = 8900g
   Density of mixture = 8900g/cm³/₁₀₅₀₀