Usually, we do not walk or even stand on a lightweight boat or raft because of the danger of falling into the water. If you have ever stepped off a small boat onto a dock, however, you have probably noticed that the boat moves away from the dock as you step toward the dock or out of the boat. A heavy dog running on a long lightweight raft presents a similar situation. At first, the raft and the dog are at rest with respect to the water (see figure A below) so that vi = 0.The dog then runs on top of the raft at vd = vd with respect to the water (see figure B below). The dog has half the mass of the raft. Find an expression for the velocity of the raft after the dog began running. (Use the following as necessary: vd.) vr =?i

Usually, we do not walk or even stand on a lightweight boat or raft because of the danger of falling into the water. If you have ever stepped off a small boat onto a dock, however, you have probably noticed that the boat moves away from the dock as you step toward the dock or out of the boat. A heavy dog running on a long lightweight raft presents a similar situation. At first, the raft and the dog are at rest with respect to the water (see figure A below) so that vi = 0.The dog then runs on top of the raft at vd = vd with respect to the water (see figure B below). The dog has half the mass of the raft. Find an expression for the velocity of the raft after the dog began running. (Use the following as necessary: vd.) vr =?i

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter10: Systems Of Particles And Conservation Of Momentum

Section: Chapter Questions

Problem 62PQ: An astronaut out on a spacewalk to construct a new section of the International Space Station walks...

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