Question

10m cubed of air weigh 13 kg.The weight of air is directly proportional to its volume. Find the constant of variation; it is called density

Answer 1

k = 1.3

let the weight be w and volume be V, then

since weight is directly proportional to volume

w = kV ← k is the constant of variation, hence

k = $\frac{w}{V}$

using the given condition, then

k = $\frac{13}{10}$ = 1.3