MOTION
THE LAWS OF NEWTON
Ostmann Science
Kate Bond Middle School
In Newtons lingua…
1. Every body perseveres in its state of rest, or of
uniform motion in a right line, unless it is
compelled to change that state by forces
impressed thereon.
2. The alteration of motion is ever proportional to
the motive force impressed; and is made in the
direction of the right line in which that force is
impressed.
3. To every action there is always opposed an
equal and opposite reaction: or the mutual
actions of two bodies upon each other are
always equal, and directed to contrary parts.
NEWTONS FIRST LAW
IS ALSO CALLED…
LAW OF INERTIA
Tendency to stay the
same
GIANT SNOWBALL
SOCCER BALL STAYS
AT REST UNTIL
PLAYER KICKS IT!
NEWTON’S SECOND LAW
How quickly an object changes speed depends on it’s mass and the
magnitude of the force acting on it.
F=mxa
OR
a = F/ m
Mass stayed the same
a = F/ m
Force got smaller
The second law is an equation that relates force,
mass, and acceleration.
NEWTONS THIRD LAW
For every action...
…there is as an equal and opposite…
…REACTION.
The third law in SPACE
MASS VS. WEIGHT
WEIGHT
MASS
A measurement of an
object’s force.
A measurement of
how much matter an
object has.
Whose mass is greater, the man on the earth or the moon?
TRICK QUESTION!
YOUR MASS IS THE SAME ON THE MOON AS IT IS ON EARTH.
Speed vs. Velocity
Displacement
Same start and end point =
didn’t go anywhere
Velocity = 0 m/s
Distance
Speed = 17.08 m/s
Horse won the race by
traveling
17.08meter/second over
10 meters
SPEED
Describes how fast an object
is moving.
VELOCITY
HOW FAST AN OBJECT IS MOVING IN
A CERTAIN DIRECTION
MOMENTUM
= (MASS) X (VELOCITY)
The force an object has due to it’s movement.
Object must be moving.
The larger the mass, the greater the momentum
VELOCITY
VELOCITY
The greater the velocity, the greater the momentum.
RAP
Laws of Motion:
RAP
HOMEWORK:
Write your own song, rap, poem or story about Newton’s Laws of Motion.
Your composition must include the following:
1. Explanation of Law 1
2. Example of Law 1 from everyday life
3. Explanation of Law 2 ( must include the equation F=m*a)
4. Example of Law 2 from everyday life
5. Explanation of Law 3
6. Example of Law 3 from everyday life
DUE: TOMORROW!
Case Study: Luciano’s Pound Puppies
HOMEWORK:
QUESTIONS TO CONSIDER WHILE
WATCHING THE VIDEO
1. What forces do you see in the
video?
2. Why does the dog slide down the
slide?
3. Which of Newton's Laws applies
when the dog jumps off of
Luciano?
4. What is an example of Newton's
First Law?
5. What is an example of Newton's
Third Law?
Circus Physics
DOGS
Digging Deeper:
Newton’s 1st law
QUESTION:
Why doesn’t the dog fall to the
ground while he leaps through
the hoop?
HE HAS INERTIA
Gravity
The dog will keep
moving until a force
like gravity pulls him
down.
Gravity pulls on the dog at a
constant rate downward.
Uninterrupted forward force
Digging
Deeper:
Newton’s 2nd
Law
The dog’s net force pulls him down the slide.
How fast is his acceleration
as he slides down?
To find the dog's acceleration, we can use Newton's 2nd Law:
Net Force = Mass x Acceleration OR "F = ma".
Digging Deeper:
Newton’s 3rd Law
HINTs:
Luciano and the dog
experience the same force.
F = ma
M = 80kg
a=?
m = 15 kg
A = 2.45 m/s2
Lucky the dog jumps off of
Luciano, causing Lucky to
momentarily accelerate
horizontally at 2.45 m/s2.
If the dog has a mass of 15 kg
and Luciano has a mass of 80 kg,
what horizontal acceleration
does Luciano feel?
Mxa=mxA
(80kg)a = (15kg)(2.45m/s2)
a = (15kg)(2.45m/s2)
80kg
Journal Assessment
Write a paragraph summarizing this presentation.
Your summary must be at least TEN sentences long to get full credit.
Use your notes to help you remember the concepts addressed in the
presentation.
Remember to include introductory and conclusion sentences.
If you are confused about a topic, write your question in the summary.