Respuesta :

Answer:

Explanation:

F = ma

Assuming the 20° is angle θ measured to the horizontal

mgsinθ - μmgcosθ = ma

g(sinθ - μcosθ) = a

at constant velocity, a = 0

g(sinθ - μcosθ) = 0

   sinθ - μcosθ = 0

                 sinθ = μcosθ

μ = sinθ/cosθ

μ = tanθ

μ = tan20

μ = 0.3639702342...

μ = 0.36