# Cycle A4 Calendar

Date

Topics

Assignment

Mon, Mar 29

A4 - 23 days - ends Apr 28

## Welcome Back!

• Review - Work:
• Ch 8 (p. 262) #109-115odd
• Ch 9 (p. 298) #37, 39, 43, 45 (Note: The y-axis passes through m1 and m3, not m1 and m4.), 47
Tue, Mar 30

Ch 9 Rotation

• 9-3 Calculating the Moment of Inertia
• Rotational inertia of a particle
• Iparticle = mr2
• Rotational inertia of a system of particles
• Rotational inertia of an extended body
• Parallel Axis Theorem: I = Icm + Mh2
• Moment of Inertia of Common Shapes (Table 9-1, p. 274)
• 9-4 Newton's Second Law for Rotation
• Torque - "turning force"
• depends on:
• amount of force
• more force more rotational acceleration
• direction of force
• force perpendicular to radius - maximum acceleration
• force parallel to radius - no acceleration
• where the force is applied
• more radius - more rot. acceleration
• Calculating torque
• (see Fig. 9-18 p. 280)
• Actually
• direction: right-hand rule (torque is an axial vector)
• in problem solving, counterclockwise is +, clockwise is - (by convention)
• Even though torque has units N.m, torque is not measured in Joules - torque is a vector, work is a scalar.
• Torque = force times "lever arm"
• Newton's Second Law:
• 9-5 Applications of Newton's Second Law for Rotation
• Note: You have to account not only for all of the forces on an object, but where on the object the forces are applied
• Rod pivoted at one end (see examples 9-6 and 9-9)
• Accelerating a flywheel (see example 9-8)
• Massive pulleys (see examples 9-10 and 9-11)
• 9-4 and 9-5
• Work:
• Ch 9 #68-71, 73
• Answers: 68) (a) v = 3.95 m/s, (b) 49.3 rad/s 70) v = 2.79 m/s, = 34.9 rad/s

Wed, Mar 31

(Mr. S absent)

Work Day
• Catch up on your assignments.

Thu, Apr 1

9-6 Rolling Objects

• "Rolling without slipping" concepts
• the role of friction
• motion of:
• the point of contact between the wheel and surface
• the center of the wheel
• the top of the wheel
• point of contact
• center of the wheel (rotation + translation)
• Kinetic energy of a rolling object
• Objects rolling up and down inclines
• Who wins the race between a disk, a sphere, and a hoop?
• Conservation of Energy approach
• Newton's Second Law approach (What is the friction force?)
• Rolling with slipping - the bowling ball problem
• initial conditions - the effect of friction
• time for which
• 9.6
• Work:
• Ch 9 #79-87odd

Fri, Apr 2

Chapter 10 Conservation of Angular Momentum

• 10-1 The Vector Nature of Rotation (review for us)
• Right-hand rule
• Cross product
• 10-2 Torque and Angular Momentum
• Angular Momentum, L, of a particle
• For a particle moving in a circle, p = mv, so we would like .
• In general,
• direction of L - use right-hand rule
• Linear Rotational
(see note 1)
(see note 2)
• Note 1: This is Newton's Second Law:
• Note 2: This is Newton's Second Law for Rotation:
• 10-1 and 10-2
• Ch. 10 #1-9odd, 43-46
• Answers: 44a) 28.0 kg m2/s, 44b) 32 kg m2, 44c) 0.875 rad/s

Mon, Apr 5

Ch 10 Conservation of Angular Momentum

• 10-3 Conservation of Angular Momentum
• From Newton's 2nd Law for Rotation: , so if the net torque on an object (system) is zero, the rate of change of its angular momentum will be zero.
• In other words, if the net torque on a system is zero, its angular momentum will not change.
• Skaters and divers
• Conservation of Angular Momentum in a bicycle wheel
• Vector nature of angular momentum
• Summary of Linear and Rotational Dynamics Equations
• 10-3
• Work:
• Ch 10 #12, 49, 51, 55, 57
Tue, Apr 6

Ch 11 Gravity

• 11-1 Kepler’s Laws
• First Law - Orbits are ellipses with sun at one focuw
• Second Law - Radius vector sweeps out equal areas in equal times
• Third Law - T2 = kr3
• mean distance = length of semi-major axis
• 11-2 Newton’s Law of Universal Gravitation
• Derivation of Kepler's Laws
• 11-3 Gravitational Potential Energy
• Using a graph of gravitational potential energy
• Escape energy
• Escape velocity
• Energy in a circular orbit
• 11-4 The Gravitational Field and g
• g as a measure of gravitational field strength
• Ch 11
• Work:
• Ch 11 #1-9odd, 15, 17, 21, 23, 37, 43-49odd, 53, 57, 59

Wed, Apr 7

Ch 11 Gravity (continued)
• Finish the Ch 11 assignment
Thu, Apr 8
Fri, Apr 9

Mon, Apr 12

Tue, Apr 13

Ch 12 - Static Equilibrium

• Conditions for static equilibrium:
• Fnet = 0 in both the x and y directions
• Examples
• 12-1 - 12-3
• Work:
• Ch 12 #1, 2 (ans: false), 9, 14 (ans: 1.4 m), 28 (ans: (a) Forces are T1, T2, and FH, (b) 139 N), 49

Wed, Apr 14

Ch 14 Oscillations

• Simple Harmonic Motion (SHM)
• If the net force on an object is a Hooke's Law force (Fnet = -kx), the object will move in simple harmonic motion.
• Where:
• SHM and circular motion
• Examples
• 14-1
• Work:
• Ch. 14 #1, 3, 23-27 odd

Thu, Apr 15

Ch 14 Oscillations

• 14-2 Energy in SHM
• 14-3 Some Oscillating Systems
• The simple pendulum
• The physical pendulum
• 14-2 and 14-3
• Work (The last assignment in AP Physics):
• Ch 14 #57, 60. 61, 67

Fri, Apr 16

Convo Schedule:

3rd block: 12:14-1:19
P.P.: 1:19-1:25
4th block: 1:25-2:30

### Ketchup Day

Mon, Apr 19

Tue, Apr 20

Wed, Apr 21

Thu, Apr 22

Fri, Apr 23

Mon, Apr 26

Tue, Apr 27

Wed, Apr 28

End of A4 - 20 days

Last update by JL Stanbrough