A rock is tied to a string and spun in a circle of radius 1.5 m as shown in Figure P5.24. The speed of the rock is 10 m/s.

(a) Draw a picture giving both a top view and a side view of the motion of the rock.

(b) What are all the forces acting on the rock? Add them to your pictures in part (a). Then draw a free-body diagram for the rock.

(c) What is the total force on the rock directed toward the center of its circular path? Express your answer in terms of the (unknown) tension T in the string.

(d) Apply Newton’s second law along both the vertical and the horizontal direction and find the angle θ the string makes with the horizontal.

Figure P5.24