Two frictionless carts are on a horizontal track. The first cart is initially at rest, and has a mass of 0.500 kg. It has a massless spring for a bumper (with spring constant 400 N/m). The second cart (mass of 0.800 kg), heads towards it from the left with a velocity of 2.00 m/s. a) What speed do the two carts have when they are travelling at the same speed

At a certain instant after jumping from the airplane a, a skydiver b is in the position shown and has reached a terminal (constant) speed vb = 52 m/s. the airplane has the same constant speed va = 52 m/s, and after a period of level flight is just beginning to follow the circular path shown of radius ρa = 2330 m. (a) determine the velocity and acceleration of the airplane relative to the skydiver. (b) determine the time rate of change of the speed vr of the airplane and the radius of curvature ρr of its path, both as observed by the nonrotating skydiver.