Julie is an avid skydiver. She has more than 300 jumps under her belt and has mastered the art of making adjustmentsto her body position in the air to control how fast she falls. If she arches her back and points her belly toward theground, she reaches a terminal velocity of approximately 120 mph (176 ft/sec). If, instead, she orients her body withher head straight down, she falls faster, reaching a terminal velocity of 150 mph (220 ft/sec).Since Julie will be moving (falling) in a downward direction, we assume the downward direction is positive to simplifyour calculations. Julie executes her jumps from an altitude of 12,500 ft. After she exits the aircraft, she immediatelystarts falling at a velocity given by v(t) = 32t. She continues to accelerate according to this velocity function until shereaches terminal velocity. After she reaches terminal velocity, her speed remains constant until she pulls her ripcordand slows down to land.On her first jump of the day, Julie orients herself in the slower “belly doWn" position (terminal velocity is 176 ft/sec).Using this information, answer the following questions. On Julie's second jump of the day, she decides she wants to fall a little faster and orients herself in the "headdown" position. Her terminal velocity in this position is 220 ft/sec. Answer these questions based on thisvelocity:5. How long does it take Julie to reach terminal velocity in this case?6. Before pulling her ripcord, Julie reorients her body in the "belly down" position so she is not moving quite asfast when her parachute opens. If she begins this maneuver at an altitude of 4000 ft, how long does she spendin a free fall before beginning the reorientation?Some jumpers wear “ wingsuits" (see Figure 1.31). These suits have fabric panels between the arms and legsand allow the wearer to glide around in a free fall, much like a flying squirrel. (Indeed, the suits are sometimescalled “flying squirrel suits.") When wearing these suits, terminal velocity can be reduced to about 30 mph (44ft/sec), allowing the wearers a much longer time in the air. Wingsuit flyers still use parachutes to land; althoughthe vertical velocities are within the margin of safety, horizontal velocities can exceed 70 mph, much too fastto land safely.Figure 1.31 The fabric panels on the arms and legs of a wingsuit work to reduce the vertical velocity of askydiver's fall. (credit: Richard Schneider)Answer the following question based on the velocity in a wingsuit.7. If Julie dons a wingsuit before her third jump of the day, and she pulls her ripcord at an altitude of 3000 ft, howlong does she get to spend gliding around in the air?

Terminal velocity is the maximum speed attained by the object as it falls through fluid/air.…

Answered: Julie is an avid skydiver. She has more…

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