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A plane lands at a speed of 38 km/s and comes to rest (0m/s) 36.3 seconds later. What is the acceleration during landing?

20 points!!!!!!!!

User TeamDman
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Acceleration = (change in speed) / (time for the change)

Change in speed = (speed at the end) - (speed at the beginning)

Change in speed = (0 km/sec) - (38 km/sec) = -38 km/sec

Acceleration = (-38 km/sec) / (36.3 sec) = -1,046.8 m/s²

Now, before we split up our points and go home, let's see what we've actually got here.

-- The plane's landing speed is about 111 times the speed of sound !

-- It rolls to rest 36.3 seconds after it touches down at this speed.

-- In order to do that, it pulls about 107 G's !

It seems to me that during the ground roll, the flight crew's eyeballs fall out, then they get ripped out of their seat belts and crash through the windshield, and the plane continues on with no life forms aboard. Then, maybe 1 second later, the drogue parachute tears off, the tires on the landing gear blow out and get shredded, the remaining fuel sloshes through the walls of the tanks and evaporates catastrophically, the wings fall off and scrape along the ground in a shower of sparks, the cloud of fuel vapor ignites and then erupts in a ball of flame, the people downtown notice it on the horizon and marvel at it, and then any remaining flaming pieces of the plane come to rest in the dense pine forest and the apartment complex 2 miles past the end of the runway.

This is not my business. I only used the numbers you gave me in the question. My math and physics are flawless, I gave you a theoretically bullet-proof answer, and this is a privilege and a pleasure for you and will stand you in good stead. You're welcome.

User TylerBrinkley
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