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Projectile motion
The curved path that an
object follows when
thrown, launched, or
otherwise projected
near the surface of the
Earth.
Centripetal force:
An
unbalanced force meaning
“towards the center” that causes
objects to move in a circular path.
Inertia
The
tendency of an object to
resist a change in motion until
acted on by an unbalanced force
.
Action/reaction pairs
All
forces act in pairs
The action of one object causes the
equal and opposite reaction of the
other
Momentum
“Mass
in motion”; the product of
the mass and velocity of an object.
Law of Conservation of Momentum
Any
time that objects collide, the
total momentum will stay the same
Newton’s First Law:
An object at rest will stay at rest and an
object in motion will stay in motion until
acted on by an unbalanced force.
Newton’s Second Law:
Acceleration depends on force and mass
How
is it expressed mathematically?
A = F/m
Example : Pushing a shopping cart full of groceries
requires more force than an empty cart if you want to
keep the acceleration the same
Newton’s Third Law:
For
every action there is an equal and
opposite reaction example: rocket
What gives an object in projectile motion it’s
vertical motion?
Gravity
If you are shooting an arrow trying to hit the
bulls eye of a target, explain where you must
aim the arrow and why.
You must aim higher than the bulls
eye because you need to account for
gravity impacting the vertical motion
and pulling the arrow down.
Provide an example of an object in projectile
motion.
Frog
jumping
Ball being thrown
Bullet being shot
Explain the motion of an unsecured object in
a car traveling at 100 miles per hour and the
brakes are suddenly slammed on – use
scientific terms we have learned!
The
object will continue to move
forward because of inertia. It will
keep moving until acted on by an
unbalanced force(like hitting the
windshield)
Name two factors that influence an object’s
inertia.
Mass
and friction
Calculate the acceleration of a 40 kg object
that is pushed with a 2N force.
a
= F/m
a = 2 kg X m/s2

40 kg
 a = .05 m/s2
Calculate the acceleration of a 80 kg object
that is pushed with a 2N force.
a
= F/m
a = 2 kg X m/s2

80 kg
 a = .025 m/s2
What happens to an object’s acceleration if
the mass increases and the force remains the
same?
Acceleration
will increase
What happens to an object’s acceleration as
the force increases, but the mass remains the
same?
Acceleration
will increase
Provide an example of an action-reaction
pair.
Baseball
bat hitting ball
Bowling ball hitting pins
Rocket blasting off
Balloon car moving
What can happen to momentum when 2
objects collide?
All
or some of the momentum
will be transferred to the other
object
Which of Newton’s Laws does each of the
following examples apply to?
1 A bicyclist
flying over the handle
bars when the brakes are applied
suddenly.
3 A rocket blasting off
2 A woman pushing a baby carriage
with a 4 kg baby in it.
Which will require more force to accelerate
an object at the same rate, a bowling ball or a
golf ball? Explain why.
A
bowling ball will require more force
because it has more mass.
If a bus and a bike are traveling with the
same velocity do they have the same
momentum? Explain your answer.
A
bus will have more momentum
because it has a larger mass than the
bike does.
Use Newton’s law of inertia, centripetal
force and gravity to explain why planets
orbit the Sun.
The
inertia that planets have (left
over from the big bang) that causes
it to “want” t travel away is balanced
by the gravitiation force of the Sun
which causes a centripetal force and
causes the planets to orbit the Sun.