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Problem 9.7: Determine the relative velocities of the boats

your velocity along the shore: v = m/s

Please wait for the animation to completely load.

Assume you are sitting on the shore of a lake and observe two boats (not shown to scale) drifting in the lake. Another student is riding in one of the boats (position is given in meters and time is given in seconds). Restart.

  1. For each of the animations, find the velocity of each boat as seen from the shore.
  2. Determine the velocity of the red boat as seen by the student riding in the green boat for each of the animations. This is the relative velocity between the two boats.

You can simulate running along the shore by typing a velocity, -15 m/s < v < 15 m/s, into the input field before you select an animation.

  1. Does changing the reference frame, i.e., running along the shore, change the relative velocities of the two boats? Try reference frame velocities of +2 m/s and -2 m/s.
  2. For each of the animations, what velocity should you enter so that the red boat appears stationary?
  3. For each of the animations, what velocity should you enter so that the green boat appears stationary?
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