Two Snowy Peaks Two snowy peaks are h = 795 m and 750 m above the valley between

Question

Two Snowy Peaks Two snowy peaks are h = 795 m and 750 m above the valley between them. A ski run extends down from the top of the higher peak and then back up to the top of the lower one, with a total length of 3.1 km and an average slope of 30° (Fig. 10-49).

Figure 10-49
(a) A skier starts from rest at the top of the higher peak. At what speed will he arrive at the top of the lower peak if he just coasts without using the poles? Ignore friction.
m/s
(b) Approximately what coefficient of kinetic friction between snow and skis would make him stop just at the top of the lower peak?

Explanation / Answer

a) conservation of energy. m*g*795=m*g*750+m*v^2/2 so v=sqrt(2*g*45)=29.7(m/s). b) friction force. Fk=mg*cos30*k. so we have mg*795=mg*750+mg*cos30*k*3.1e3 so 45=cos30*k*3.1e3 so k=0.017

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.