..above horizontal? Suppose that μk = 0.35.
Constant speed means Fnet = 0.
Let m = mass of wood block and Θ = angle of ramp then
if µk = 0.35:
Fnet = 0 = mg(sin Θ) – (µk)(mg)(cos Θ)
mg(sin Θ) = µk(mg)(cos Θ)
µk = tan Θ
Θ = arctan(µk) = arctan (0.35) ≈ 19.3° ANS