Thinking Critically Answer the following questions. Use complete sentences. You can use diagrams to help explain your answer. 1. A wrench is being used at an angle 20 from the perpendicular. Explain why the angle 70 is used in the equation when calculating torque. 2. Explain how a force of 20 N causes an object to rotate Irrad in 1 s, but another force of 20 N using the same lever arm can cause the same object to rotate 3% rad in 1 s. 3. Explain why the formulas for calculating the moment of inertia are different for objects of different shapes. 4. Which vehicle would be more stable on a sharp turn in the road: a minivan or a sports car? Explain your answer. 5. When observing the effects ofthe Coriolis "force,\" why is only the horizontal aspect of the motion considered? Why doesn't the Coriolis "force" affect vertical motion? Circle the letter of the choice that best completes the statement or answers the question. 1. Which ofthe following choices is a unit used to measure an object's rotation? a. radian c. newton b. meter d. kilogram 2. A rotating disc has a knob on the edge of it. The disk completes a rotation every 3 5. Using this information, you can calculate the angular of the knob. a. acceleration c. measure b. displacement d. speed 3. The perpendicular distance from the axis of rotation to the point where a force is exerted is the _. a. lever arm c. net torque b. moment of inertia d. torque 4. In addition to the amount of mass present, the _ of that mass is also needed to determine the amount of torque needed to change angular velocity. 3. density c. moment of inertia b. location d. weight 5. According to Newton's second law for rotational motion, an object's angular acceleration equals the a. net torque multiplied by the moment of inertia b. net moment of inertia divided by the net torque c. net torque divided by the moment of inertia d. net torque added to the moment of inertia 6. Under which of the following conditions will static equilibrium not exist for an object? a. when both its velocity and angular velocity are zero b. when the net torque is not zero c. when the object is in rotational equilibrium d. when the object is in translational equilibrium 7. What is apparently observed as centrifugal "force" is instead the effect of a. angularacceleration c. centripetalacceleration b. Coriolis \"force\" d. centripetal force 8. If a person is standing at the center of a rotating disk and throws a ball towards the edge of the disk, the ball will appear to be following a Curved horizontal path by a person who is a. observing the vertical motion of the ball b. standing on a ladder above the disk c. standing on the disk d. standing to the side of the disk 9. The Coriolis "force" makes winds rotate _ in the southern hemisphere. a. clockwise around low-pressure areas b. counterclockwise around low-pressure areas c. clockwise around high-pressure areas d. counterclockwise around high-pressure areas Complete each statement by writing the correct term in the bionic provided. 10. As an object rotates, the change in the angle is called 11. If the angular velocity of an object is positive, it is rotating 12. Marci and Juan are on opposite ends of a seesaw. Although they have different masses, the seesaw balances because the net torque is 13. The measure of how much an object resists rotation is that object's 14. Newton's second law of rotational motion states that angular acceleration is directly proportional to the 15. The axis of rotation for a uniform, spinning disc is located at the of the disc. 16. For an object to be in static equilibrium, it must be in equilibrium, which means that the net torque on the object must be zero. 17. Newton's laws do not apply to rotating frames of reference because these frames are frames. 18. The lower the center of mass of an object is located, the greater the of that object. 19. If a projectile is thrown to the north from the equator, the horizontal motion of the projectile would also have a{n) component