Download FORCE:

FORCE:
“Any influence that can cause a body to be accelerated. It is
measured in NEWTONS.”
*A push or pull exerted by an object to/on another object;
*Always occurs in pairs- Agent & Receiver
*It can alter the shape or motion of an object;
*It is represented by arrows that show direction and size.
NEWTON’S THREE LAWS OF MOTION:
Law #1.
Every body continues in its state of rest, or of uniform motion in a
straight line, unless it is compelled to change that state by forces
impressed upon it.
Sometimes called the “Law of Inertia.”
INERTIA: The sluggishness or apparent resistance a body offers
to changes in its state of motion.
MASS:
The quantity of matter in a body.
It is the measurement of Inertia.
m = F/a
F = m(a)
MOMENTUM:
The product of MASS and VELOCITY.
a = F/m
It is inertia in motion.
CONSERVATION OF MOMENTUM:
All energy stored in a moving object is not lost, but only changes
form.
Mass in a Circular Motion
ROTATIONAL INERTIA:
(AKA: Gyroscopic Inertia)
“An object rotating about an axis tends to remain rotating about
that same axis unless it is interfered with by some external force.”
*This definition is similar to Newton’s First Law of Motion.
ANGULAR MOMENTUM:
A measure of an object’s rotation about a particular axis.
For an object small compared to the radial distance, it
is the product of mass, velocity and radius.
It is the measure of the rotational property of motion.
It is always perpendicular to the centripetal force.
CENTRIPETAL FORCE:
A center-seeking force that causes an object to follow a circular
path.
“Any force that is directed at right angles to the path of the moving
body and produces circular motion.”
The following formulas are similar to those for Newton’s First Law,
but deal with mass in motion in a circular path:
mv
r = mvr
total mass is not affected by a
smaller radius, while velocity is...
v ?
m
r=
vr
What happens in this situation?
CENTRIFUGAL FORCE:
A fictitious outward force due to rotation. It is a reaction to
centripetal force but there is no agent, therefore it is experienced
relative to position.
LAW #2:
The acceleration of a body is directly proportional to the net force
acting on the body and inversely proportional to the mass of the
body and is in the direction of the NET FORCE.
a = F/m
F = m (a)
m = F/a
In other words:
If force is = you increase mass, then acceleration decreases;
If mass is = you increase force, then acceleration increases
LAW #3:
Whenever one body exerts a force on a second body, the second
body exerts an equal and opposite force on the first.
For every action, there is an equal and opposite reaction;
You cannot touch without being touched.
Other Physics concepts of interest:
ENERGY:
The quality of an object that enables it to do work.
Power = WORK/ TIME
POTENTIAL ENERGY:
The stored energy that a body possesses because of its position
with respect to other bodies.
KINETIC ENERGY:
The energy of motion.
Kinetic Energy = 1/2 mv2
P
K
As an object falls, it’s energy transfers
from Potential to Kinesthetic.
Q: At what point would both of these
be equal?
P
K