Six crates(a, b,c, d,e, f) at rest on level surfaces. The crates have differentmasses and the frictional coefficients [given as(μs,μk)] between the crates and the surfaces differ. Thesame external force is applied to each crate, but none of thecrates move.

Rank the crates on the basis of thefrictional force acting on them.
Rank from largest to smallest.

a. [500kg μ=(0.6,0.3)]

b. [750kg μ=(0.4,0.3) ]

c. [250kg μ=(0.2,0.1)]

d.[600kg μ=(0.8,0.5)]

e.[750kg μ=(0.6,0.5)]

f. [1500kg μ=(0.3,0.1) ]