A `30 kg` mass is initially at rest on floor of a truck . The coefficient of static friction between the mass and the floor of truck in `0.3` and coefficient of kinetic friction is `0.2` . Initially the truck is travelling due east at constant speed.Find the magnitude and direction of the friction force acting on the mass , if : (take `g = 10 m//s^(2))`
(a) the truck acceleration at `1.8 m//s^(2)` eastward
(b) the truck acceleration at `3.8 m//s^(2)` westward

Answer

[54 N, 59 N]