The side of a soil embankment has a 45° slope (Fig. a). If the coefficient of static frict...

The side of a soil embankment has a 45° slope (Fig. a). If the coefficient of static friction of soil on soil is μs = 0.6, will the embankment be stable or will it collapse? If it will collapse, what is the smallest slope that can be stable?

Strategy: Draw a free-body diagram by isolating part of the embankment as shown in Fig.

(a)

(b)