A vertical spring of constant k = 400 N/m hangs at rest. When a 2 kg mass is attached to it, and it is released, the spring extends downwards before bouncing back up. What it is the maximum extension that the spring will have before it changes direction? Answer in cm

If we relied solely on the nonrenewable resources found in the u. s., which one would we run out of first at current usage levels? a. natural gas b. oil c. uranium d. coal

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.

Which of the following forces require physical contact? tension air resistance friction magnetic force applied force