Question

A relative density bottle weighs 0.03kg when empty and 0.057kg when full of water. What will it weigh when full of kerosene of relative density 0.8?

Answer 1

The mass of the kerosene is,
`M_(k)` = 0.021 kg

Step-by-step explanation:

Given data,

The mass of the empty density bottle, m₁ = 0.03 kg

The mass of density bottle filled with water, m₂ = 0.057 kg

The relative density of kerosene is, ρ = 0.8

`\rho = (density of kerosine)/(density of water)`

Density of kerosene = Density of water x relative density

= 1000 kg/m³ x 0.8

= 800 kg/m³

The mass of water in the bottle,

`M_(w)` = m₂ - m₁

= 0.057 kg - 0.03 kg

= 0.027 kg

The volume of bottle,

`V =  (M_(w))/(\rho)`

`V =  (0.027)/(1000)`

V = 2.7 x 10⁻⁵ m³

The mass of the kerosene,

`M_(k) = \rho_(k) * V`

`M_(k)` = 800 x 2.7 x 10⁻⁵

= 0.021 kg

Hence, the mass of the kerosene is,
`M_(k)` = 0.021 kg