Answer
(a) The belt exerts a static frictional force on an apple.
(b) $\mu_s = 0.40$
Work Step by Step
(a) Since the apples do not slide on the conveyor belt, the belt exerts a static frictional force on an apple.
(b) We can find the coefficient of static friction:
$F_N~\mu_s = 0.40~N$
$\mu_s = \frac{0.40~N}{F_N}$
$\mu_s = \frac{0.40~N}{1.0~N}$
$\mu_s = 0.40$
