The Nexia car was filled with 40 liters of gasoline. How much energy will be released per kilometer

The Nexia car was filled with 40 liters of gasoline. How much energy will be released per kilometer with an average gas consumption of 7 liters per 100 km. The density of gasoline is 710 kg / m ^ 3 ..

1) The volume of gasoline that is consumed to travel 1 km:

V = Р / 100, where Р – gasoline consumption per 100 km (Р = 7 liters).

V = 7/100 = 0.07 l = 0.07 dm3 = 0.07 * 10 ^ -3 m3.

2) The mass of gasoline to travel 1 km:

m = ρ * V, where ρ is the density of gasoline (ρ = 710 kg / m3).

m = 710 * 0.07 * 10 ^ -3 = 0.0497 kg.

3) Released energy:

Q = q * m, where q is the specific heat capacity of gasoline (we take q = 4.6 * 10 ^ 7 J / kg).

Q = 4.6 * 10 ^ 7 * 0.0497 = 2,286,200 J ≈ 2.3 MJ.

Answer: 2.3 MJ of energy will be released per kilometer.