Jack and Jill are doing a physics lab. They apply a 15 Newton force to a 3 kg cart to pull it up an inclined plane at a constant speed. The plane in inclinee at a 30 degree angle. Jack and Jill are exerting a force on the cart which is parallel to the inclined plane in order to displace it 2.0 meters along the incline to a final height of 1 meter. During this lab, how many Joules of work was done on the cart?

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.