1. the coefficient of kinetic friction between an object and the surface upon which it is sliding is
0.25. the weight of the object is 20n. what is the force of friction?

Force of friction in the given question is 5 N

Given that;

Coefficient of kinetic friction μ = 0.25

Weight of the object = 20N

Find:

Force of friction

Computation:

Force of friction = Coefficient of kinetic friction μ × Weight of the object

Force of friction = 0.25  ×  20

Force of friction = 5 N

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5 N

Explanation:

Friction force is normal force times coefficient of friction

F = Fn μ

On level ground, normal force equals weight.

Fn = W

Substitute:

F = Wμ

F = (20 N) (0.25)

F = 5 N

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards