The 0.20 kg puck on the frictionless, horizontal table in Figure P6.51 is connected by a string

Question:

The 0.20 kg puck on the frictionless, horizontal table in Figure P6.51 is connected by a string through a hole in the table to a hanging 1.20 kg block. With what speed must the puck rotate in a circle of radius 0.50 m if the block is to remain hanging at rest?

r = 0.50 m FIGURE P6.51 0.20 kg 1.20 kg