(adsbygoogle = window.adsbygoogle || []).push({}); 1. You are a member of an alpine rescue team and must project a box of supplies, with mass m, up an incline of constant slope angle alpha so that it reaches a stranded skier who is a vertical distance h above the bottom of the incline. The incline is slippery, but there is some friction present, with kinetic friction coefficient mu_k.

Use the work-energy theorem to calculate the minimum speed v that you must give the box at the bottom of the incline so that it will reach the skier.

Express your answer in terms of some or all of the variables m, g, h, mu_k, and alpha.

2. K_final = 0

K_initial = 0.5mv^2

net work = F(delta r)*cos(theta)

3. Normal force = mg

Force in x direction = mg[-mu_k - sin(alpha)]

net work = K_final - K_initial

= -0.5mv^2

= F(delta r)*cos(alpha)

= -mg[mu_k + sin(alpha)]*h*cos(alpha)

finally:

v = sqrt[2gh(mu_k + sin(alpha))*cos(alpha)]

Apparently my trigonometry is wrong (i.e. I have a cos and/or sin mixed up), but I am not sure where my error is.

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# Work-energy theorem problem - I have it close to correct

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