Please help solve Problem 11.68 Part C

If the car gets 15 miles per gallon when driving on sand, what is the car's efficiency? One gallon of gasoline contains 1.4 x 108 J of chemical energy, one mile is 1609 m. Express your answer as a percentage. Driving on asphalt roads entails very little rolling resistance, so most of the energy of the engine goes to overcoming air resistance. But driving slowly in dry sand is another story. If a 1300 kg car V AEd ? is driven in sand at 4.7 m/s , the coefficient of rolling friction is 0.060. In this case, nearly all of the e = energy that the car uses to move goes to 1.4 % overcoming rolling friction, so you can ignore air drag in this problem. Submit Previous Answers Request Answer . X Incorrect; Try Again; 5 attempts remaining A Provide Feedback Next