SECTION 1 Impulse and Momentum In your textbook, read about relating impulse and momentum. The diagram shows the forcetime graph for a force acting on a 12.0kg cart initially at rest on a frictionless surface. Use the diagram to answer questions 18. Show your calculations where necessary. 20.0 18.0 .0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0100 Time (a) 1. What is the magnitude of the force acting on the cart? 2. How long does the force act on the cart? 3. The shaded area of the graph represents 4. The algebraic expression that represents the shaded area ofthe graph is 5. What is the amount of impulse acting on the cart? 6. The algebraic expression that represents the momentum of the cart is 7. How large is the change in momentum ofthe cart? 8. The final velocity of the cart is MOMENTUM AND ITS CONSERVATION Vocabulary Review Write the term that correctly completes the statement. Use each term once. angular impulse-angular momentum theorem impulse-momentum theorem momentum isolated system angular momentum law of conservation of angular momentum closed system impulse 1. law of conservation of momentum The product of a rotating object's moment of inertia and its angular velocity is the ofthe object. The states that the momentum ofany closed, isolated system does not change. The states that the angular impulse on an object equals the difference in the object's final and initial angular momenta. The states that an object's initial angular momentum equals its final angular momentum when no external torque acts on the object. In a(n) , mass in neither gained nor lost. The product ofthe average force on an object and the time interval over which it acts is . In a(n) , no net external force is exerted on the system. When mass is multiplied by velocity, the answer is a measure of The states that the impulse on an object is equal to the change in the object's momentum. In your textbook, read about using the impulse-momentum theorem. Read each statement below. For each situation, calculate Vi V Pi Pt the impulse vector FAt, and the amount of force needed for the change to occur. All situations refer to a truck with a mass of 2840 kg. Assume that the forward direction is positive. 9. The truck has a velocity of 8.30 m/s and comes to a stop in 15.0 s. 10. The truck, initially at rest, reaches a velocity of 8.30 m/s in 20.0 s. 11. The truck is at rest. In 5.00 s, the truck backs up to a speed of 1.38 m/s. 12. The truck is moving backward with a velocity of 1.38 m/s and comes to a stop in 5.00 s. In your textbook, read about the impulse-momentum theorem as it applies to air bags. Answer the following questions. Use complete sentences. 13. List two ways in which impulse can be increased. 14. How does an air bag reduce injuries that would be caused by the steering wheel during an accident? Write your answer in terms of impulse