Captain John Stapp of the U. S. Air Force tested the human limits of acceleration by riding on a rocket sled of his own design. His rocket sled, known as the Gee Whiz, had a mass of about 95 kg. What net force would be required to accelerate the
Gee Whiz and 82-kg Stapp at 450 m/s/s (a. k.a. m/s?) which is the highest acceleration tested by Stapp?

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?