a 35 kg child slides down a 26 degree incline. the coefficient of kinetic friction is 0.33. what is her speed after sliding for 2.5 seconds starting from rest?

Answer 1

Wc = M*g = 35*9.8 = 343 N.

Fp = 343*sin26 = 150.4 N. = Force parallel to the incline.

Fn = 343*Cos26 = 308.3 N. = Normal.

Fp-Fk = M*a.
150.4-0.33*308.3 = 35*a.
35a = 48.66.
a = 1.39 m/s^2.

V = Vo + a*t = 0 + 1.39*2.5 = 3.48 m/s.