2. (c) It changes with changes in the temperature. (d) It increases if the concentration of one of the reactants is increased. A) Work is positive on the way up, work is positive on the way down B) Work is negative on the way up, work is negative on the way down C) Work is negative on the way up, work is positive on the way down D) Work is positive on the way up, work is negative on the way down E) Work is zero the way up, work is zero on the way down _(25) What happens to the kinetic energy of a moving object if the net work done is positive? A. The kinetic energy increases B. The kinetic energy decreases C. The kinetic energy remains the same D. The kinetic energy is zero E. The kinetic energy becomes negative rt II. Problem Solving. 3. 5. (e) It may be changed by the addition of a catalyst. (23) Electric charge, electric potential, energy, temperature etc. are examples of (c) Both a) Scalar quantity (b) Vector quantity (d) None (24) An object is thrown straight up. Which of the following is true about the sign of work done by the gravitational force while the object moves up and then down? 1. A non-uniform is 4.5 m long and weighs 640 N. It is balance when a 270 n weight is hung 0.80 m from the light end of the bar and the bar is pivoted at its center. Where is the center of gravity of the bar? The posible answer is t.com from heavy End Two workers carry a non-uniform beam weighing 730 n. The beam is 2.6 m long and its center of gravity is 1.1 m from one end. If the workers hold the beam at its end, how much does each worker lift? Find the angular displacement in radians during the second 20-s interval of a wheel that accelerates from rest to 725 revolutions per minutes in 1.50 minutes. . Show Complete solution and illustration is required. 5 Points each 4. A Flywheel accelerates uniformly from rest to an angular velocity of 15 revolutions per seconds in 6.0 s. What is the angular accelera the flywheel in revolution per second square? Radians per second square? And degrees per second square? In the diagram, a rope is threaded around three pulleys of radii, R1 = 0.30 m, R2 = 0.20 m, and R3= 0.10 m. There is no slippage. (a) If the rope moves with constant speed v = 5.0 m/s, what is the angular velocity of each pulley? What is the frequency and period of each pulley? (b) The rope accelerates from 5.0 m/s to 10.0 m/s in 10.0 s, what is the average angular velocity of each pulley for this time? What is the average angular acceleration of each pulley? How many revolutions does each pulley turn in that 10.0 s? DFUL