Starting from rest, a 5.2-kg blockslides 2.40 m down a rough 30.0°incline. The c

Question

Starting from rest, a 5.2-kg blockslides 2.40 m down a rough 30.0°incline. The coefficient of kinetic friction between the block andthe incline is µk = 0.436. (a) Determine the work done by the force ofgravity.
1 J

(b) Determine the work done by the friction force between block andincline.
2 J

(c) Determine the work done by the normal force.
3 J

(d) Qualitatively, how would the answers change if a shorter rampat steeper angle were used to span the same vertical height?
4 (a) Determine the work done by the force ofgravity.
1 J

(b) Determine the work done by the friction force between block andincline.
2 J

(c) Determine the work done by the normal force.
3 J

(d) Qualitatively, how would the answers change if a shorter rampat steeper angle were used to span the same vertical height?
4

Explanation / Answer

Wg = work done by gravity = m g h h = 2.4 sin 30 = 1.2 Wg = 5.2 * 9.8 * 1.2 = 61.2 J Wf = N d = m g d cos       work done by frictionalforce where N is normal force Wf = .436 * 5.2 * 9.8 * 2.4 cos 30 = 46.2 J WN = 0       since the normal force does no work From the formulas Wg increases if increases because the changein height is greater Wf decreases because the normal forcedecreases WN remains zero

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

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