The carton shown in Fig. 4-55 lies on a plane tilted at an angle = 25.0° to the horizontal, with µk = 0.07.

(a) Determine the acceleration of the carton as it slides down the plane.

m/s2 (down the plane)

(b) If the carton starts from rest 8.70 m up the plane from its base, what will be the carton's speed when it reaches the bottom of the incline?

m/s

The carton shown in Fig. 4-55 lies on a plane tilted at an angle = 25.0° to the horizontal, with μk = 0.07.
(a)

Ff – mgsinθ = ma

μkmgcosθ – mgsinθ = ma you can factor the m on the left side and they cancel, so

μkgcosθ – gsinθ = a

(b)

vf^2 = vi^2 + 2ad

vf^2 = 0 + (the answer from part a)*d then take the square root

vf = sqrt(2ad)