Askydiver jumps out of a hovering helicopter, so there is no forward velocity.

just as the skydiver steps out of the helicopter, someone who’s watching starts a stopwatch. so the time is zero as the skydiver steps out of the plane. what is the skydiver’s downward velocity at that instant, just before starting to fall?

In a load, the load is paralel to the shaft. n a. angular n b. thrust n c radial n d. none of the above

The ratio of lift to drag l/d for a wing or airfoil is an important aerodynamic parameter, indeed, it is a direct measure of the aerodynamic efficiency of the wing. if a wing is pitched through a range of angle of attack, l/d first increases, then goes through a maximum, and then decreases. consider an infinite wing with an naca 2412 airfoil. estimate the maximum value of l/d. assume that the reynolds number is 9x10^6.

Which situation will produce the greatest change of momentum