Three people are floating on a 127-kg raft in the middle of a pond on a warm sum

Question

Three people are floating on a 127-kg raft in the middle of a pond on a warm summer day. They decide to go swimming, and all jump off the raft at the same time and from evenly spaced positions around the perimeter of the raft. One person, with a mass of 62 kg, jumps off the raft at a speed of 10 m/s. The second person, of mass 73 kg, jumps off the raft at a speed of 8 m/s. The third person, of mass 53 kg, jumps off the raft at a speed of 12 m/s. At what speed does the raft drift from its original position?

Explanation / Answer

M = 127-kg, m1 = 62 kg, v1 = 14 m/s, m2 = 73 kg, v2 = 8 m/s, m3 = 52 kg, v3 = 13 m/s. find the final speed v of the raft. choose direction of v1 as x axis initial speed = 0, so initial momentum = 0 x component of final momentum = m1*v1 - m2*v2*cos(60) - m3*v3*cos(60) + Mvx = 0 vx = [-m1*v1 + m2*v2*cos(60) + m3*v3*cos(60)]/M = -1.874 m/s y component of final momentum = m2*v2*sin(60) - m3*v3*sin(60) + Mvy = 0 vy = [-m2*v2*sin(60) + m3*v3*sin(60)]/M = 0.6274 m/s v = sqrt(vx^2 + vy^2) = 1.976 m/s

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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