Dynamics Acceleration Notes
When things do move in response to forces, we have what we call
dynamics. Then there is an acceleration.
Lets consider a common situation: riding an elevator
You are in an elevator at rest on the ground floor.
Inertial mass Notes
Here for the first time we encounter mass. Note that mass
relates acceleration to resultant force: the bigger the acceleration
for the same force, the smaller the mass. This property of matter
is actually called inertial mass.
We did n
Newton Laws of Motion Notes
Now that we have learned how to describe motion, how do we
cause the motion that we want?
We apply forces on an object!
But what do forces directly affect:
location? velocity? acceleration?
Newton answered these questions by po
Mass of the Earth Notes
The great gravity we feel on the earth is due to the huge mass of
the earth. Even though gravity is weak, the huge mass of the
earth combines lots of very weak forces into one reasonably
But how much mass does the ear
Gravitational Force Notes
Previously we saw that the force of gravity depended on the
mass of an object as well as the constant acceleration due to
But we know that objects on the moon fall to the moons
surface, not to the earths surface. If o
Relative Velocity Notes
How do we work with a situation in which an object moves on
something that is itself moving?
Examples: Flying an airplane in air that is moving (flying in a
wind), running a boat on the river, walking inside an airplane that
Satellites Concepts Notes
The same concepts (equations):
Fgravity = msat acircular
where Fgravity = GMearthmsat/Rsat2 and
acircular = w2Rsat can be used to determine the period of a satellite
in orbit around the earth, or determine the radius the satellit
Substituting in the knowns with Algebra Notes
x = xo + vxt
y = yo + vyot + (1/2)ayt2
vy = vyo + ayt
Substituting in the knowns, we have:
x = (0 m) + (25.28 m/s * t)
0 m = (12 m) + (21.21 m/s*t) + (1/2 *-9.8 m/s2*t2)
vy = (21.21 m/s) + (-9.8 m/s2 * t)
Zero acceleration Statistics Notes
Statics is the name for situations in which there is zero
Example: consider the situation below where two ropes hold
up a weight:
qright = 55o
W = 100 Nt
Example of Statics
What is t
Uniform Circular Motion Rectangular viewpoint Notes
Circular motion is defined by: r = constant.
Uniform circular motion is defined by:
d/dt = w = constant, so dq = w dt; upon integration o d = 0t w
dt, or q - qo = wt,
so we have q = qo + wt.
Two Dimensional Motion Notes
How do we work with two dimensions when we consider
We work with vectors by working with the components!
Does it matter which form we use: rectangular or polar?
Since vectors add nicely in rectangular, we need to work
The previous example was showing how we could predict where
the ball was going to go based on how we threw it.
We can also determine how to throw a ball so that it hits where
we want it to. This is the point of the computer homework
Uniform Circular Motion Notes
Even though the radius is constant, the angle changes. For right
now, we will consider the special case where the angle changes
at a constant rate. This type of motion is called uniform circular
Note that since the ra