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## Homework Statement

A skier of mass 67 kg is pulled up a slope by a motor-driven cable.

(a) How much work is required to pull him 40 m up a 30° slope (assumed frictionless) at a constant speed of 1.7 m/s?

m= 67kg

Delta y= 40m

Theta= 30 degrees

v= 1.7m/s

## Homework Equations

I know that:

F=ma

W= F cos(Theta) (Delta y)

## The Attempt at a Solution

I am solving for the force:

F=ma

F= 67 (1.7)

F= 113.9 N/m

With F solved I use my Work Equation:

W= F cos(Theta)(Delta y)

W= 113.9 (cos30) (40)

W= 3945.61 J

W= 3900 J

My answer differs from the correct answer by 10% to 100%

What am I doing wrong? Am I using the wrong equations?