1. Instructor: Dr. Tatiana Erukhimova
Physics 218: Mechanics
Instructor: Dr. Tatiana Erukhimova
Lectures 38, 39, 40
Hw: Chapter 15 problems and exercises

2. For symmetrical objects rotating about their axis of symmetry:
Second Law:

3. The rope is assumed not to slip as the pulley turns
The rope is assumed not to slip as the pulley turns. Given m1, m2, R, and I find the acceleration of mass m1. I m1 m2 R

4. Two masses, and , are attached by a massless, unstretchable string which passes over a pulley with radius R and moment of inertia about its axis I. The horizontal surface is frictionless. The rope is assumed NOT to slip as the pulley turns. Find the acceleration of mass

5. A solid sphere rolls down an inclined plane of angle θ without slipping.
a) Find the acceleration of the sphere.
b) Find the maximum θ if the coefficient of static friction is μ.

6. Gyroscopic precession
The precession of a gyroscope shows up in many “common” situations.

7. A rotating flywheel

8. Conservation of Momentum
If the collision is perfectly elastic, the kinetic energy is conserved!

9. Circular Motion y x

10. Torque and Angular Momentum
Conservation of Angular Momentum

12. Test 3 results Average 65.6 Median 69.5 30 23 20 16 15 10 7 >90
>80
>70
>60
>50
>40
<40

13. Ch. 17 Statics

14. Ch. 17 Statics Parallel-Axis Theorem
A rigid body has a lower moment of inertia about an axis through its center of mass than about any other parallel axis

15. There is a ladder against a wall
There is a ladder against a wall. There is no friction at the wall and the coefficient of friction at the floor is . At what angle can the ladder be placed so that it would slip if the angle were decreased infinitesimally?

16. The advantage of a lever
GIVE ME A PLACE TO STAND AND I WILL MOVE THE EARTH                                                  

19. Have a great day!