Question

One gallon of gasoline releases approximately 1.1 108 J when it is "burned" (i.e., undergoes combustion) in a car engine. If the engine releases 4.9 107 J of heat during this time, what is the mechanical work done by the engine? ANSWER IN J Unit

Answer 1

First law of thermodynamics: In any thermodynamic process, the net heat absorbed by a system is equal to the sum of the net work done by the system and the change in the internal energy of the system.

      E = Q + W

        W= E – Q

            =1.1×10⁸ J – 4.9×10⁷ J

            =6.1×10⁷ J