Ablock of mass 2.5 kg is attached to a spring with spring constant 150 n/m and slides on a rough, horizontal surface (coefficient of kinetic friction 0.25). the spring is initially extended by a distance of 45 cm from its equilibrium position and released from rest. (a) what is the speed of the block when it is at the equilibrium position of the spring? (b) where does the block stop?

Review multiple-concept example 7 in this chapter as an aid in solving this problem. in a fast-pitch softball game the pitcher is impressive to watch, as she delivers a pitch by rapidly whirling her arm around so that the ball in her hand moves in a circle. in one instance, the radius of the circle is 0.626 m. at one point on this circle, the ball has an angular acceleration of 66.1 rad/s2 and an angular speed of 12.6 rad/s. (a) find the magnitude of the total acceleration (centripetal plus tangential) of the ball. (b) determine the angle of the total acceleration relative to the radial direction.