05_InstSolManual_PDF_Part17 - and m k2 5 m k1 1 v 02 v 01 2...

5.36.
Set Up: Use to find the acceleration that can be given to the car by the kinetic friction force. Then
use a constant acceleration equation. Take in the direction the car is moving.
Solve: (a) The free-body diagram for the car is shown in Figure 5.36. gives gives
and Then and gives
Figure 5.36
(b)
5.37.
Set Up: The free-body diagram for the car is shown in Figure 5.37.
Figure 5.37
Solve: Relate a to gives gives and Use a
kinematic equation to relate a to the stopping distance d . (stops),
gives Same means and
and so
Reflect: The stopping distance is proportional to the acceleration and the acceleration is proportional to the friction
force, so the stopping distance is decreased by the same factor as is the coefficient of friction.
5.38.
Set Up: The free-body diagram for the car is given in Figure 5.37.
Solve: As in Problem 5.37, Same D means
and