A parachutist whose mass is 80 kg drops from a helicopter hovering 1000 m above the...

A parachutist whose mass is 80 kg drops from a helicopter hovering 1000 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 = 30 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 20 m/sec, after how many seconds will the parachutist reach the ground? Assume that the acceleration due to gravity is 9.81 m/sec²

The parachutist will reach the ground after ______ seconds.
(Round to two decimal places as needed.)

Expert Solution

genius_generous answered 2 years ago

A parachutist whose mass is 80 kg drops from a helicopter hovering 2000 m above the...

A parachutist whose mass is 80 kg drops from a helicopter hovering 2000 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=100 N-sec/m when the chute is open. If the chute does not open until the velocity of the parachutist reaches 35 m/sec, after how many...

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