Unformatted text preview: 44 Chapt. 4 Two- and Three-Dimensional Kinematics 8. Deep in the Amazonian jungle you wish to cross a river livid with piranha and crocodiles. Let x be the coordinate ALONG the river and y the coordinate PERPENDICULAR to the river. The river width is y max = 20 m. You are going to paddle across (on an unstable rotting log—using your bare hands) and your paddling speed is v paddle = 0 . 50 m / s. a) How long does it take you to cross assuming that you (wisely) aim straight in the y- direction? b) Assuming the river flows at a steady velocity v x = 0 . 20 m / s how far downstream (i.e., in the x direction) have you gone while crossing? c) What is your velocity relative to the shore during the crossing? Give this velocity in magnitude-direction format. HINT: Remember to specify direction. d) Now let’s make the not-too-likely assumption that the river velocity in the x-direction is a linear function of y , the distance in the y-direction. Let v x ( y ) = v x max y y max , where y = 0 at the starting shore and...
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- Fall '06
- Physics, Velocity, River, Coordinate system, Spherical coordinate system, Polar coordinate system, Cylindrical coordinate system