the fuel tank of a truck has a capacity of 55 gal. if the tank is full of gasoline (sg=0.751)

Question

sg=0.751

 

find mass and weight of the gasoline in SI units

Answer 1

55 gal x 0.751 g/gal = 41 grams

SI unit of mass = kg, so mass = 41 g x 1 kg/1000 g = 0.041 kg

SI unit of weight is Newtons, so weight = 0.041 kg x 9.8 N/kg = 0.40 Newtons (on earth)

Both answers are given to 2 significant figures.