A pendulum of mass 22 kg is released from rest at some height, as shown by point A in the image below. At the bottom of its arc at point B, it is traveling at
a speed of 13 m/s. What is the approximate amount of energy that has been
lost due to friction and air resistance? (Recall that g = 9.8 m/s2)

Diego is trying to lift a piano to the second floor of his house. diego uses a pulley system and gives a big lift to the piano. the piano moves upward, then stops, and then it starts to fall to the ground. which list best describes the forces on the piano in the proper order? a.positive force, balanced force, negative force b.negative force, balanced force, positive force c.positive force, unbalanced force, negative force d. negative force, unbalanced force, positive force