10-03- 11
Agenda
HOMEWORK CHECK
Place on your desk:
*Calculator
*Orange homework chart
*Newton’s 1st Law Reading Assignment
 1) What is (2.0 X 102)(3.0X103)=
6.0X105
 2) Convert 5.5X 105 g to Kg in scientific
notation. KHD G DCM
5.5X102 Kg
1) Warm-Up
5 min
2) Pick-Up Fill-in-blank, Vocab.,
Orange Chart
3) Vocab. Words 5 min
4) Newton’s First Law 15 min
5) Formula Sheet 5 min
6) Newton’s 1st Law Worksheet
45 min
Vocab.
1. Force: any push or pull; measured in Newton’s
(N); can be any of the main basic types: friction,
weight, tension, stretch, normal force, etc.
2. Friction: force that acts between materials that
touch as they move past each other; acts
parallel to the surface in contact & opposite the
motion
3. Inertia: resisting change in its state of motion;
property of all bodies of matter.
4. Kilogram: SI unit of mass
• Forces affect motion. A force is a physics
quantity that can affect the state of motion of
an object.
• A force is any push or pull. Since forces have
magnitude & direction, and can be combined
with other forces, it is a vector quantity.
• The study of forces which cause motion is
called dynamics and the relationship of force,
mass and motion are described by Newton’s
Law of Motion.
A. Characteristics of forces
1. Net forces will change the state of motion of
an object (application of a net force to an
object always produces acceleration)
2. Can be exerted through long distances
3. Occurs in pairs
4. Each pair, each force works opposite of the
other—can be balanced or unbalanced.
Types of forces
Net force, normal force (acts at right angles),
equilibrant force, friction, weight, fluid forces,
air resistance, pressure etc.
-Unit of measurement for all forces is the
Newton (N) which is equal to the mass of the
object times the amount of gravity acting on
the mass:
1 N=1Kg (9.8 m/s2)=N 1 N=9.8 Kg m/s2
***F=mg
-Instrument used to measure forces is spring
scale.
-Instrument measures the amount of stretch
which is proportional to the force pulling on
the spring or equal to the amount of force
acting on the spring as long as its restoring
strength is intact (Hooke’s Law)
-Friction
Force of friction depends on the kinds of
materials in contact & how many surfaces are
pressed together; fluid friction is found in
fluids (liquids & gases); air resistance which is
friction due to movement in the air—noticed
at high speeds.
Friction tends to balance the applied force & give
a net foce of zero (0)
-Pressure
Pressure is the amount of force per unit area & is
measured in Pa (pascals)
-Free Fall—force of gravity
If friction is neglected, objects of different mass
will fall at the same rate of acceleration due
to the same amount of gravity acting on the
objects.
-1st law of Motion: Law of Inertia
Law deals with the motion on which NO net
force is acting.
Law says “If there is no net force acting on a
body, it will continue in its state of rest or will
continue moving along a straight line with
constant speed.”
(Things tend to keep on doing what they are
already doing or in the absence of forces, a
moving object tends to move in a straight line
indefinitely)
Forces which have an influence on this law are
friction and inertia (property of matter that
opposes a change in its state of motion– the
greater the mass, the greater the inertia).
Inertia keeps a stationary object stationary & a
moving object moving. This law specifies the
form of motion possible: constant motion in a
straight line is only possible if the object is far
removed from the other objects & variable
motion is caused by the presence of some
other object.
DUE TODAY:
• Newton’s 1st law Notes (KEEP)
• Newton’s 1st law Worksheet
“Beauty is eternity gazing at itself in a
mirror.”
Khalil Gibran
DUE NEXT CLASS:
• Newton’s 1st law worksheet
• Bring Calculator!