Question

The fuel tank of a large truck measures 1.2m x 0.9m x 0.6m. If it takes 12 minutes to fill the tank at a garage fuel pump. What is the mass flow rate of fuel from the pump, assume the relative density of the fuel is 0.8?

Answer 1

Answer: 43.8 kg/min

Volume of the fuel = Volume of the tank=$1.2 m\times0.9 m\times0.6 m=0.648 m^3$

Here, we are considering that the given relative density is with respect to water.

Density of fuel =Relative Density of fuel ×Density of water

Density of fuel$=0.8\times1000kg/m^3=800kg/m^3$

Mass of the fuel filled= Density of fuel ×Volume of the fuel

Mass of the fuel filled$=800kg/m^3\times0.648m^3=518.4kg$

$Mass\hspace{1mm} flow\hspace{1mm} rate \hspace{1mm}of \hspace{1mm}the\hspace{1mm} fuel=\frac {Mass\hspace{1mm} of \hspace{1mm}the \hspace{1mm}fuel \hspace{1mm}filled}{Time\hspace{1mm} consumed \hspace{1mm}to\hspace{1mm} fill \hspace{1mm}the\hspace{1mm} fuel \hspace{1mm}in\hspace{1mm} the \hspace{1mm}tank}\\ \Rightarrow Mass \hspace{1mm}flow \hspace{1mm}rate\hspace{1mm} of \hspace{1mm}the\hspace{1mm} fuel=\frac{518.4kg}{12min}=43.8kg/min$

Hence, mass flow rate from the pump is 43.8 kg/min.