Physics quiz question: gas consumption rate

Physics 8A Quiz 1, Fall Semester 2005
Cuesta College, San Luis Obispo, CA

Physics 8A learning goal Q1.1

(Cf. Young and Freeman, University Physics, 11/e, Exercise 1.9.)

[3.0 points.] The gasoline consumption of a small sedan is advertised as 30.0 miles per gallon. Which one of the following choices best corresponds to this value in meters per milliliter?
(A) 4.93 x 10^-5 m/mL.
(B) 12.8 m/mL.
(C) 70.6 m/mL.
(D) 78.4 m/mL.

Correct answer: (B)

The gasoline consumption can be expressed in meters per milliliter using unit conversions:

(30 mi/gal) * (1.609 km/1 m) * (1,000 m/1 km) * (1 gal/3.785 L) * (1 L/1,000 mL) = 12.8 m/mL.

Response (A) is (30/(1,609*3.785)); response (C) is (30*3,785)/1,609; response (D) is 3,785/(30*1,609).

Student responses:
(A) : 28 students
(B) : 0 students
(C) : 0 students
(D) : 0 students