Calculate the maximum acceleration of a moving car so that a body lying on the floor of the car remains stationary. The coefficient of static friction between the body and the floor is $0.15$ ($g = 10\ \text{m s}^{-2}$).
$a_{\max} = \mu_s g = 0.15 \times 10 = 1.5\ \text{m s}^{-2}$.