In your textbook, read about momentum in a closed, isolated system. Write the term that correctly compfetes the statement. Use each term once. change external forces isolated system closed system interaction law of conservation of conditions internal forces momentum Mn] (4) is a system that does not gain or lose mass. Within such a system, all forces are (5) . Forces that are outside this system are (6} . This system is a(n) (7) when the net external force on it is zero. The {8) states that the momentum of the system does not {9} if the system has no net external forces acting on it. You can use this law to relate (10) before and after an interaction even if you do not know any details of the (11) . In your textbook, read about recoil. Write iess than zero, zero, or greater than zero in the bionks for questions 1215. For questions 16 and 17, circie the answer that best completes the statement. Two in-line skaters are standing still on a surface that is smooth so that there are no external forces. The first skater gives the second skater a push in one particular direction. The momentum of the system before the push is (12) .The momentum of the system after the push is (13) . The momentum of the first skater after the collision is (14) . and that of the second skater is (15) 16. The momentum of the first skater after the push can be written as pm, or it can be written as a. pg\"; (3- _pB.f b. +pB_f d. 0 17. If the velocity of the second skater after the push is represented by vi\In your textbook, read about two-dimensional collisions. Read the paragraph below. Use the momentum diagram at right, Pal indicating the final momentum of the system, pf; the momentums of pm both baiis after the collision, PM and Per; the right angle; and the 50. 0 angle. P! A 4.0-kg ball, A, is moving at a speed of 3.0 m/s. It collides with a stationary ball, B, of the same mass. After the collision, ball A moves off in a direction of 50.0 to the left of its original direc- tion. Ball B moves off in a direction of 90.0\" to the right of ball A's nal direction. For each description given, write the letter of the matching term. 18. 19. 20. 21. 22. a term that represents the total momentum of the a. (12 kg-m/s){cos 50-0") system before the collision b. 12 kg-m/s the magnitude of the total momentum of the system C- (12 kg-m/sHsin 50-0") after the collision d. Pm the magnitude of ball A's final momentum the magnitude of ball B's final momentum Skater N, 58.9 kg, is moving north at a speed of 7.8 m/s when she collides with Skater E, 72.6 kg, moving east at 3.5 m/s. The two skaters are stuck together. In what direction and with what speed do they move after the collision? Draw and label a momentum-vector diagram. Show your calculations. In your textbook, read about angular momentum. Read each statement beio w. if the statement is true, write true. if the statement is faise, rewrite the itaiicized part to make the statement true. 15. 16. 17. 18. 19. 20. 21. The moment of inertia around a given axis of a fixed, solid object cannot be changed. Linear momentum is the product of the moment of inertia and angular velocity for a rotating object. A net torque on an object results in a change in angular momentum. As an ice skater spins and pulls her arms closer to her body, her angular velocity decreases because of the change in her moment of inertia. An object's moment of inertia depends upon the distribution of mass about the axis of rotation. As each planet orbits the Sun, its angular momentum is zero because the torque on each planet is zero. A planet moves siower when its distance from the Sun decreases. SECTION 2 Conservation of Momentum In your textbook, read about two-particle collisions. Read the foiiowing sentences. Use compiete sentences to comment on items I 3. Two balls, A and B, are traveling at different speeds and have different masses. They collide head-on and rebound in opposite directions as part of a closed, isolated system. 1. 2. 3. the force that ball A exerts on ball B and the force that ball B exerts on ball A the impulses received by both balls the total momentums of the balls before the collision and after the collision