The two balls are attached to the light rigid rod, which is suspended by a cord from the support above it. If the balls and rod, initially at rest, are struck with the force F = 11.7 lb, calculate the magnitudes of the corresponding acceleration a of the mass center and the rate at which the angular velocity of the bar is changing. T 8.0" + 3.6" T 5.1" 10.2" Answers: ā= Ö= Mi Mi 4.18 lb 2.93 lb ft/sec² rad/sec²

Consider a slender rod AB with a length l and a mass m. The ends are connected to blocks of negligible mass sliding along horizontal and vertical tracks. If the rod is released with no initial velocity from a horizontal position as shown in Fig.A, determine its angular velocity after it has rotated through an angle of θ (see Fig B) using the conservation of energy method. (Hint: Moment of inertia of rod about G = (1/12)ml2 The kinetic energy of a rigid body in plane motion is

The 18-kg rod AB is pin-connected at A and subjected to a couple moment of M =15 N- m The rod is released from rest when the spring is unstretched at 0 = 30°. As the rod rotates, the spring always remains horizontal, because of the roller support at C. (Figure 1) Determine the rod' s angular velocity, measured clockwise, at the instant 0 = 60°. Express your answer using three significant figures. Enter positive value if the angular velocity is clockwise and negative value if the angular velocity is counterclockwise. vec rad/s k = 40 N/m 0.75 m M = 15 N- m

The 2.28-kg uniform slender bar rotates freely about a horizontal axis through O. The system is released from rest when it is in the horizontal position 0 = 0 where the spring is unstretched. If the bar is observed to momentarily stop in the position 0 = 66°, determine the spring constant k. For your computed value of k, what is magnitude of the angular velocity of the bar when 0 = 48°. B 0.85 m 0.85 m 2.28 kg 0.29 my Answers: k = i N/m ω- rad/s 1