A ball on a string is moving in a horizontal circle. The Radius is 2.5 meters and the velocity of the ball is 3.5m/s. The tension in the string is 5.5 N. What is the mass of the ball?

1. do the particles in the medium material move in the same direction of the wave or at opposite direction to the wave? explain your answer. 2. by inputting more energy into the wave, i. e a large shake of the spring, which wave property also increases? 3. are there forces of friction acting while a wave is passing through a medium?