How Much Work is Needed to Pull a Skier Up a Slope?

[kmart47]

a skier of mass 72.9 kg is pulled up a slope by a motor-driven cable. The acceleration due to gravity is 9.81 m/seconds squared. How much work is required to pull the skier 63.5 m up a 34 degree slope (assumed to be frictionless) at a constant speed of 2 m/seconds squared. Answer in units of J.



HELP me out please

 

[tim_lou]

calculate the change in gravitational energy.
where must this energy come from?

 

[kyle8921]

Based on the given information, we can use the equation W = Fd to calculate the work required to pull the skier up the slope. First, we need to find the force (F) required to pull the skier, which can be calculated using Newton's Second Law: F = ma, where m is the mass of the skier and a is the acceleration (2 m/seconds squared). Substituting the values, we get F = (72.9 kg)(2 m/seconds squared) = 145.8 N.

Next, we need to find the distance (d) the skier is being pulled. Since the skier is being pulled up a slope, we can use trigonometry to find the vertical distance (d) using the given angle (34 degrees) and the given horizontal distance (63.5 m). Using the formula d = x/sin(theta), where x is the horizontal distance and theta is the angle, we get d = (63.5 m)/sin(34 degrees) = 116.8 m.

Now, we can plug in the values of F and d in the work equation to get: W = (145.8 N)(116.8 m) = 17034.24 J. Therefore, the work required to pull the skier 63.5 m up a 34 degree slope at a constant speed of 2 m/seconds squared is 17034.24 J.