Question

A Skier is pulled up a slope at a constant velocity by a tow bar. The slope is inclined at 25°. The force applied to the skier by the tow bar is parallel to the slope. The skier's mass is 55.0 kg and the coefficient of kinetic friction between the skies and snow is 0.12. Find the magnitude of the force that the tow bars exert on the skier.

Answer 1

To solve your problem, we can apply Newton's second law of motion.
Fⁿ = ma 

Fnet = net force acting on the skier 
m = mass of the skier = 53 kg 
a = acceleration up the slope 

Since velocity is constant then acceleration is zero, hence the above equation becomes 

Fnet = 0 

Fnet = F - Wx - f 

where 

F = force exerted by the tow bar 
Wx = component of skier's weight parallel to the incline = 53(9.8)(sin 20) 
f = frictional force = 0.160(53)(9.8)(cos 20) 

Substituting appropriate values, 

F - 53(9.8)(sin 20) - 0.160(53)(9.8)(cos 20) = 0 

and solving for F, 

F = 99.55 N 

Hope this helps and have a nice day!