Lecture 23
New concepts
dW (t )
instantaneous work done by force F
F (t ) .
dr
Force at time t displacement of the particle between t and t dt
t final
W (tinitial , t final )
Total Work done by a force in time tinitial to t final
tinitial
dW (t )
dW (tini
Chapter 7
Newtons Third Law
Newtons Third Law (7.1)
Every force is actually a mutual interaction between two objects.
If object A exerts a force FA on B on object B, then object B exerts
an equal and opposite force FB on A on object A simultaneously. In
o
Chapter 9
Impulse and Momentum
Momentum and Impulse (9.1)
sion
Com
pres
ion
Expans
The force exerted on a particle in a collision is a complicated
function of time, Fx(t). Apply Newtons 2nd law:
dv x
Fx
max m
Fx t
dt
Multiply both sides by dt:
t
Duration
Chapter 6
Dynamics I: Motion Along a Line
Equilibrium (6.1)
If the net force on a particle is zero, then the acceleration is also
zero, and the velocity is constant. This is a state called
equilibrium.
1) Static equilibrium refers to a state in which the
Chapter 10
Energy
Kinetic and Potential Energy (10.1)
Kinetic energy is the energy an object possesses by virtue of
moving at a speed v and is given by
1 2
K mv ,
2
in units of kgm2/s2, which is called the joule (J).
Gravitational potential energy is the
Chapter 3
Vectors and Coordinate Systems
Vectors (3.1)
A vector quantity includes both magnitude (always positive) and
direction (i.e., displacement and velocity).
A
A
The arrow representing a vector shows the value of the vector
quantity only at the poin
Chapter 5
Force and Motion
Force (5.1)
A force is an influence that causes, or tends to cause, the motion
of an object to change.
Every force is exerted by some agent that does the pushing or
pulling. In the first semester of this course, every force
exer
Chapter 12
Rotation of a Rigid Body
Motions of a Rigid Body (12.1)
A rigid, extended body can execute three
different types of motion:
1) Translational motion
2)
Rotational motion
3)
Combination motion
Tangential Velocity and Angular Velocity (12.1)
Every
Chapter 1
Concepts of Motion
Motion Diagrams (1.1)
A motion diagram is a succession of snapshots taken at equal
time intervals and superimposed.
Motion Diagram Examples (1.1)
What can be known about the motion from the diagrams below?
http:/webphysics.dav
Chapter 4
Kinematics in Two Dimensions
Acceleration Vectors (4.1)
The acceleration vector always points in the same direction as
the change in velocity vector:
v
aavg
vn 1
vn 1
v
vn
t
afree fall
vn
The velocity vector can change either by changing its m
Chapter 2
Kinematics in One Dimension
Uniform Motion (2.1)
-3
-2
-1
0
+1
+2
+3
x (m)
0s
1s
2s
3s
x (m)
In uniform motion, an
object travels in a
+2
straight line, covering
equal distances during
0
ANY successive
equal-time intervals.
-2
4s
5s
6s
x
2
t (s)