Topic 7 – Rotational Motion and the Law of Gravitation

Goal: For this Topic, students will study rotational motion. Celestial motion will also be explored as Newton’s law of universal gravitation is coupled with circular motion and Newton’s laws of motion. These will then be related to Kepler’s Laws of planetary motion.

Objectives:

•        Define angular position, angular displacement, angular speed, and angular acceleration with examples.

•        Apply the equations of constant angular acceleration to solve rotational motion problems. Draw connections between the kinematic equations for linear motion under constant acceleration and kinematics equations for rotational motion under a constant angular acceleration.

•        Relate angular variables to linear variables. Describe how to calculate the tangential velocity and tangential acceleration from the corresponding angular variables.  Define and calculate the centripetal acceleration of an object undergoing circular motion.

•        Give examples of forces that produce circular motion. Recognize that centrifugal forces are fictitious forces.

•        State the law of universal gravitation, and recognize it follows an inverse square law relationship. Calculate the gravitational potential energy for an object at a large distance above the Earth’s surface. Calculate the escape speed for any planetary body. State Kepler’s three laws of planetary motion. Combine Newton’s second law, the law of universal gravitation, and centripetal acceleration to derive Kepler’s third law.

Assignments:

1. Read and Take Notes sections 7.1 – 7.2; Problems 1, 2

2. Read & Take notes section 7.3; Problems 3, 4, 5

3. Read and Take Notes sections 7.4; Problems 9, 10, 12, 16

4. Problems 17, 18;

5. Problems 23, 27

6. Read & take notes section 7.5.1 – 7.5.3; Problems 28, 32

7. Read & take notes section 7.5.4; Problems 33, 35, 36

8. Problems 41, 45, 46

9. Test Review

10. Chapter 7 Test