A parachutist whose mass is 65 kg drops from a helicopter hovering 1500 m above the ground and falls toward the ground under the influence of gravity. Assume that the force due to air resistance is proportional to the velocity of the parachutist, with the proportionality constant b₁ = 20 N-sec/m when the chute is closed and b₂ = 90 N-sec/m when the chute is open. If the chute does not open until the velocity of the parachutist reaches 25 m/sec, after how many seconds will the parachutist reach the ground? Assume that the acceleration due to gravity is 9.81 m/sec².

A parachutist whose mass is 65 kg drops from a helicopter hovering 1500 m above the ground and falls toward the ground under the influence of gravity. Assume that the force due to air resistance is proportional to the velocity of the parachutist, with the proportionality constant b₁ = 20 N-sec/m when the chute is closed and b₂ = 90 N-sec/m when the chute is open. If the chute does not open until the velocity of the parachutist reaches 25 m/sec, after how many seconds will the parachutist reach the ground? Assume that the acceleration due to gravity is 9.81 m/sec².

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter5: Displacement And Force In Two Dimensions

Section: Chapter Questions

Problem 8STP

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A parachutist whose mass is 65 kg drops from a helicopter hovering 2500 m above the ground and falls toward the ground under the influence of gravity. Assume that the force due to air resistance is proportional to the velocity of the parachutist, with the proportionality constant b_1 = 20 N*sec/m when the chute is closed and b_2 = 90 N*sec/m when the chute is open. If the chute does not open until the velocity of the parachutist reaches 25 m/sec, after how many seconds will the parachutist reach the ground? Assume that the acceleration due to gravity is 9.81 m/sec^2. How much time will the parachutist reach the ground after? (Round up your answer to two decimal places as needed.)
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