Question

Determine the force that allows you to pull a 122kg wooden sled on wet snow at a constant velocity. The coefficient of kinetic friction between wood and wet snow is 0.10.

Answer 1

120 N

Step-by-step explanation:

Draw a free body diagram. There are four forces acting on the sled:

Weight force mg pulling down,

Normal force N pushing up,

Friction force Nμ pushing left,

and applied force P pulling right.

Sum of forces in the y direction:

∑F = ma

N − mg = 0

N = mg

Sum of forces in the x direction:

∑F = ma

P − Nμ = 0

P = Nμ

P = mgμ

Plug in values:

P = (122 kg) (9.8 m/s²) (0.10)

P = 120 N