The document describes the mass, dimensions, and notation used in a problem involving the forces exerted on an automobile's wheels. It provides the mass M of the automobile, horizontal distances L between axles and from the rear axle to the center of mass, and defines the forces F1 and F2 exerted on the front and back wheels, respectively. Taking torques about the rear axle allows calculating F1 as 2.77 × 103 N, and equilibrium of forces gives an equation to solve for F2 as 3.89 × 103 N.

1. 8. Our notation is as follows: M = 1360 kg is the mass of the automobile; L = 3.05 m is the horizontal
distance between the axles; = 3.05 − 1.78 = 1.27 m is the horizontal distance from the rear axle to the
center of mass; F1 is the force exerted on each front wheel; and, F2 is the force exerted on each back
wheel.
(a) Taking torques about the rear axle, we find
Mg (1360kg) 9.8m/s2 (1.27 m)
F1 = = = 2.77 × 103 N .
2L 2(3.05 m)
(b) Equilibrium of forces leads to 2F1 + 2F2 = M g, from which we obtain F2 = 3.89 × 103 N.