[Basic Velocity] Finding velocity with x and y distances?

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To find the velocity of the plane, the parachutist's fall time from 140 meters is calculated to be approximately 5.35 seconds. Using this time, the horizontal distance of 60 meters is divided by the fall time to determine the plane's velocity, resulting in about 12 m/s. The initial approach using the Pythagorean theorem to find displacement is noted, but the correct method involves calculating time and horizontal distance for velocity. The discussion emphasizes the importance of time in determining velocity rather than solely relying on displacement. Overall, the plane's velocity is confirmed to be around 12 m/s.
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Ex. problem. A plane is flying 140m above the surface. A parachutist drops out of the plane and lands 60m from where he jumped out. What is the plane's velocity?

I used the Pythagorean theorem to find the displacement of the parachutist, i.e. the hypotenuse. I then multiplied the parachutist's displacement by two times the acceleration of gravity. The product would be some velocity squared. I don't know if this is the correct velocity, so I'm wondering how to find that.
 
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physxaffinity said:
Ex. problem. A plane is flying 140m above the surface. A parachutist drops out of the plane and lands 60m from where he jumped out. What is the plane's velocity?

I used the Pythagorean theorem to find the displacement of the parachutist, i.e. the hypotenuse. I then multiplied the parachutist's displacement by two times the acceleration of gravity. The product would be some velocity squared. I don't know if this is the correct velocity, so I'm wondering how to find that.

So, you're just guessing what the correct answer is.

The plane is flying at an altitude of 140 m. How long does it take for something to fall from that height and hit the ground?
 
Edit: It would take 5.35 seconds.
 
You've got a distance and a time now. What's the velocity of the plane?
 
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60m/5.35s = ~12m/s

Yay SteamKing! Thanks for your help.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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