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emmasim [6.3K]
3 years ago
12

Mike has a mass of 97 kg. He jumps out of a perfectly good airplane that is 2000 m above the ground. After he falls 1000 m, when

his downward speed is 68 m/s, Mike opens his parachute. The positive y-direction is downward.
(a) Calculate the average magnitude of the upward force of the air resistance on Mike during his initial descent.

(b) After Mike opens his parachute, he continues to descend, eventually reaching the ground with a speed of 4.0 m/s. Calculate the average upward force during this part of Mike's descent.

(c) At the same time Mike jumps out of the airplane, his wallet (mass of 0.3 kg) falls out of his pocket. Calculate the wallet's downward speed when it reaches the ground. For this calculation, assume that air resistance is negligible.
Physics
1 answer:
Ne4ueva [31]3 years ago
4 0

Answer:

a)  fr = 224.3 N , b)   fr = 224.3 N , c)   v = 198.0  m/s

Explanation:

a) For this exercise let's start by calculating the acceleration in the fall

             v² = v₀² - 2 a (y-y₀)

When it jumps the initial vertical speed is zero

             a = -v² / 2 (y-y₀)

             a = -68 2/2 (1000-2000)

             a = 2,312 m / s²

Let's use the second net law to enter the average friction force

            fr = m a

            fr = 97 2,312

            fr = 224.3 N

b) let's look for acceleration

            v² = v₀² - 2 a y

            a = (v² –v₀²) / 2 (y-y₀)

            a = (4² - 68²) / 2 (0-1000)

            a = 2,304 m / s²

            fr = m a

            fr = 97 2,304

            fr = 223.5 N

c) the speed of the wallet is searched with kinematics

           v² = v₀² - 2 g (y-y₀)

           v = √ (0-2 9.8 (0-2000))

           v = 198.0  m/s

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Explanation:

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Putting value of equation (2) in equation (1) the overall formula will be as follows.

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Boyle's law says that the volume of a gas varies inversely with the pressure. When the volume of a certain gas is 4l , the press
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Boyle's law says that the volume of a gas varies inversely with the pressure. When the volume of a certain gas is 4l , the pressure is 720 kpa (kilopascals). What is the pressure when the volume is 10l ?

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An ice skater is spinning at 6.00 rev/s with his moment of inertia being 0.400 kg/m2. Calculate his new moment of inertia if he
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Density of petrol= d =740 kg/m³

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density= mass/ Volume

Mass = Density × Volume

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The mass of the petrol is 22200 kg.

Total mass of tanker with petrol = Mass of petrol + Mass of tanker

Total mass of tanker with petrol= 22200+ 2800 kg

Total mass of tanker with petrol= 25000 kg

Total weight of the tanker with petrol = Mass of tanker full of petrol× g

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Total weight of the tanker with petrol= 25000×10 = 250000 N

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brainly.com/question/24100921

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