The kinetic coefficient of friction is 0.40
Kinetic friction, also known as sliding friction or gliding friction, is the slowing force between two objects moving relative to each other. This is important in understanding the dynamic friction coefficient. The dynamic coefficient of friction is the pulling force required to keep an object in motion divided by the pulling force on the two sliding surfaces. This factor is specific to the materials involved in the contact surfaces. The rougher the surface, the higher the coefficient.
Calculation:
given
mass =10kg
force(Ff)=40N
so
Ff=μ F=μmg
40=μ*10*9.8
μ=0.40
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