L ECTURE 4: N EWTON S 1 ST AND 2 ND L AWS
Newtons 1st Law of Motion
Mass/inertia
Newtons 2nd Law of Motion
Net Force
Free-body diagrams
1. Roughly estimate the speed of a long bomb thrown by a quarterback in
m/s. (Hint: v = s/t, where s is the change
L ECTURE 5: N EWTON S 3 RD L AW
Newtons 2nd (review)
Newtons 3rd law of motion
Distinguishing the 2nd and 3rd laws
Damage in collisions
1. A strong offensive lineman pushes the defensive lineman straight back.
If the net force is doubled, the accelera
L ECTURE 6: P ROPERTIES OF VARIOUS F ORCES
Gravity
Normal force
Friction
Elastic forces
For gravity, the force is proportional to the mass
Hewitt.
Acceleration due to gravity is independent of mass
Hewitt
Air resistance can obscure that g=constant
Wil
L ECTURE 7: R OTATIONAL K INEMATICS ( DESCRIBING
ANGULAR MOTION )
Angular motion
Circular motion
Centripetal/centrifugal force
Combined translational and rotational motion
Decomposition
Spin
Units of angular displacement
1. A basketball announcer sa
L ECTURE 8: F LUID F ORCES
Buoyancy
Drag & Lift
Cross-sectional area
Density
Speed
Laminar and turbulent ow
Curveballs
Midterm information
The buoyant force
Hay
Drag depends upon cross-sectional area
Hay
Goalies want a large cross-sectional area
H
L ECTURE 9: E NERGY
Work
Kinetic Energy
Potential Energy
Conservation of Energy
Work is Force times Distance, W = Fd
Wilson
Is Work done here?
Wilson
Only the force parallel to the motion counts towards Work
Wilson
Kinetic Energy depends on Mass and S
L ECTURE 10: E NERGY IN ATHLETES
Information on grades
Energy conservation in the human body
Power
Metabolism
Heat dissipation
1. Which of these is not a form of energy?
(a) Work F d
(b) Gravitational potential energy mgh
1
(c) Kinetic energy 2 mv2
(
L ECTURE 11: M OMENTUM & C OLLISIONS
Momentum (Newtons Laws revisited)
1. p = mv is constant (when no F)
2. Impulse F t = p
3. Conservation of momentum ptotal = 0
Elastic & inelastic collisions
Bounces
Coefcient of restitution
Oblique angle
Spin
Mom
1) In water polo, a soft throw often splats when it
bounces on the water but a hard throw usually skips.
Which one is the best answer?
A. The coefficient of restitution is small for the splat but large for the skip.
B. The coefficient of restitution is la
L ECTURE 13: F LEXIBLE BODIES AND R OTATIONAL
D YNAMICS
Center of gravity (center of mass)
Rotational inertia (moment of inertia)
Rotational dynamics
For translational motion and calculating torques, the mass of a
ruler acts as if it were concentrated
L ECTURE 14: A NGULAR M OMENTUM
Rotational dynamics (review)
Conservation of angular momentum
Altering total I
Altering which parts rotate
Turning without any initial L
Rotational energy
Kinetic energy
Work
a)
b)
c)
d)
a)
1) The formula for angula
L ECTURE 15: A PPLICATIONS OF A NGULAR M OTION
T HEORY
Rotational impulse (billiards)
Transition to rolling
Balance
Stability
Translational/Rotational Analogs
Translational
Rotational
Mass m
Rotational inertia I
Position x, y, .
Angle , .
Velocity v
A
L ECTURE 16: H ITTING ( SWING & TARGET )
Swing maximizes Mv of club
Strike ball in sweet spot
minimize motion at handle
minimize vibrational energy
recover elastic energy
Big I of club improves accuracy
BEFORE IMPACT
AT IMPACT
normal
2
1
v2'
2
2
v1
L ECTURE 17: H ITTING (D ESIRED T RAJECTORY )
Hitting review (powerful swing)
Recoil velocity
Relative & center-of-mass velocity
Recoil angle and spin
Effect of normal force
Effect of friction
Projectile motion with drag and lift
The Register
1. Wh
L ECTURE 18: S AILING +
Sailing
Wave drag & Surface Tension
Sliding/Rolling (revisited)
More trajectories
In a corner kick, the perpendicular force is horizontal
Hay.
What do we call the force that curves the ball to the right in the video?
Which fo
L ECTURE 19: R EVIEW AND O VERVIEW
Unanswered questions
Philosophical Interlude
More unanswered questions
Final logistics
Car Questions
1. In a rear wheel drive car, why does the rear end of the vehicle attempt to
pull in front of the front end, resul
L ECTURE 3: P ROJECTILE M OTION
More Vector addition
Moving thrower
Completing a pass
Monkey & hunter
Range (projectile motion)
Optimal launch angles
To maximize range
To minimize response time (catching a projectile)
To maximize accuracy
Vectors
L ECTURE 2: J UMPING AND V ECTORS
Free Fall
Jumping
Vectors & Components
Vector Addition
Relative motion
Completing a pass
Graphical Analysis of Position, Velocity, and Acceleration
Halliday & Resnick
Tabular and Algebraic Analysis:
Hewitt.
v = at
T
Physics 17 2008 Final
Fill in Bubble A in the Test Form box.
1. An ice skater pulls her arms in to spin faster. Of these four quantitiesangular velocity , angular
momentum L, kinetic energy K , and rotational inertia I which quantity decreases?
(a)
(b) L
Homework #1
Due midnight Sunday September 25.
1. Give a sports example of an object that travels a large distance but has a
small displacement.
2. Can you give a sports example wherein the acceleration of an object is
opposite to the direction of its velo
Homework #2
Due midnight Sunday October 2.
1. In Fig. 3-6 of Hay, which ball has
(a) the smallest speed?
(b) the greatest launch angle ?
(c) the largest horizontal component of the velocity?
(d) the largest vertical component of the velocity?
2. The gures
Homework #3
Due midnight Sunday October 9.
1. Use the ideas of inertia and Newtons 1st and 2nd laws to explain why
oensive lineman in football are huge but running backs are not.
2. What is the net force on the blocking sled in Fig. 5-6c? What direction
d
Homework #4
Due midnight Sunday October 16.
1. Answer these True/False questions. (No explanations required.)
(a) The normal force exerted on a particular object always has the same
magnitude.
(b) The normal force is always perpendicular to the surface th
Homework #5
Due midnight Sunday October 23.
1. Give an example of a sport where the buoyant force is used to reduce drag.
2. The drag force is F = CA(v 2 /2). Give sports examples that illustrate
the importance of each of the four terms on the right-hand
Homework #6
Due midnight Sunday October 30.
1. Changes in energy for the human body can be described by the equation:
Change in Internal Energy = Chemical EnergyMechanical WorkDissipated Heat.
(1)
Connect each of the following activities with a term in th