A 50.0 kg ice skater is standing at rest on the ice holding a 2.0 kg medicine ball. She throws the medicine ball to the right with a horizontal velocity of 1.8 m/s. What is the velocity of the skater after she throws the ball?

Arope has one end tied to a vertical support. you hold the other end so that the rope is horizontal. if you move the end of the rope back and forth with a frequency of 4 hz, the transverse wave you produce has a wavelength of 0.5 m. what is the speed of the wave in the rope?