Question

Determine the maximum acceleration of the train in which a box lying on its floor will remain stationary. It is given that the coefficient of static friction between the box and the floor of the train is 0.13. (g = 9.8m/s²)

Answer 1

Given ; μ_s = 0.13; g = 9.8m/s²; a_max =?
The frictional force acting between the floor of the train and the surface of the box, will oppose the slipping of the box on the floor of the train.
∴ Limiting friction force
f_s = ma_max
and f_s = μ_sN = μ_smg

∴ m.a_max = μ_smg
or a_max = μ_sg = 0.13 × 9.8
or a_max = 1.274 ms^-2
or a_max = 127 ms^-2