98 points, 5 simple look up luke aikins no parachute 25,000 feet airplane jump complete video on yt it is a 3 min video and i will put my questions down here then. how high was his jump in meters? assuming luke has a mass of 90kg how much potential energy does he have just as he leaves the plane? explain how you know. with what force does gravity pull him toward the earth? explain how you know. what is his acceleration just as he leaves the plane? explain how you know. if there was no wind resistance how fast would luke be going just before he hits the net? explain how you know.

This is a fun question - your science teacher is creative!

First is easy, 25000 feet converts to 7620 meters

Potential energy is a product of mass, gravity and height. In this case, mass is 90Kg and height is 7620m. gravity on earth is 9.8m/s2.

Potential energy = 90(9.8)(7620) = 6720840J

By Newton 2nd law, force is equal to mass times acceleration.

Gravity force = mass*gravity

= 90(9.8) = 882N

Acceleration when he leaves the plane is gravity, 9.8m/s2

With no wind resistance, the acceleration is constant at 9.8.

Using kinematic equation, v2 = u2 + 2as where u is initial velocity, v is final velocity, a is acceleration and s is distance traveled.

In this case, u=0, a=9.8, s=7620

v^2 = 2(9.8)(762) = 149352

final velocity = sqrt (149352) = 386.5m/s