Download Name: Newton`s First Law of Motion: The Law of Inertia “An object at

Name: ___________________________
Newton’s First Law of Motion: The Law of Inertia
“An object at rest remains at rest and an object in motion remains in motion at a constant speed and in a straight
line unless acted on by an unbalanced force.”
Part 1: An object won’t _______________ moving unless an _______________ force ( a _______________ or a
_______________) is exerted on it.”
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The golf ball is at _______________ until the golfer applies an _______________ force to it with the club.
Part 2: An object _______________ a certain _______________ will continue to move forevere at the same
_______________ and in the _______________ direction unless some _______________ force acts on it.
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The baseball will keep _______________ until the catcher applies an _______________ force to it with his
glove.
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According to Newton’s First Law, this ball will keep rolling at the _______________ speed and in the
_______________ direction unless an _______________ force acts on it.
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_______________ provides the _______________ force that will eventually make the ball
_______________.
All images are from clipart.com and Stop Faking It: Force & Motion by William C. Robertson
Newton’s First Law is called the Law of Inertia
_______________ is the tendency of all objects to _______________ any _______________ in motion.
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Objects will remain at _______________ due to inertia (part 1 of the law).
Objects will remain in _______________ due to inertia (part 2 of th law).
Inertia is why it is _______________ for a plane, car or bike to _______________ instantaneously.
_______________ is a measure of _______________.
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A _______________ mass = a _______________ inertia
A _______________ mass = a _______________ inertia
It is easier to push a _______________ to get it in _______________ than it is a _______________.
It is harder to stop a _______________ ball than it is to stop a _______________ ball moving at the same
_______________.
Newton’s Second Law of Motion: Force = Mass x Acceleration
“ The acceleration of an object depends on the mass of the object and the amount of force applied.”
Part 1: _______________ Depends on _______________
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For the same _______________, an object’s acceleration _______________ as its mass _______________
and its acceleration _______________ as its mass _______________.
Part 2: _______________ Depends on _______________
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An object’s acceleration _______________ as the force on it _______________.
An object’s acceleration _______________ as the force on it _______________.
Acceleration of an object is always in the_______________direction as the _______________ applied.
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If you want two _______________ objects to have the _______________ acceleration, the object with
the _______________ mass will require a _______________ force.
Formulas for Newton’s Second Law of Motion:
F
Force = Mass x Acceleration
1 kg m/s/s = 1 Newton
m
a
Example Problems:
1.
What force is necessary to accelerate an 1250 kg car at a rate of 40 m/s/s?
2. What is the acceleration of a 7 kg mass if a force of 68.8 N is used to move it towards Earth?
3. What is the mass of an object if a force of 34 N produces an acceleration of 4 m/s/s?
This formula explains why all objects accelerate towards Earth at 9.8 m/s/s no matter what their mass is.
a=F
m
a=1N
0.102 kg
a = 9.8 m/s/s
a=F
m
a = 10 N
1.02 kg
a = 9.8 m/s/s
Newton’s Third Law of Motion: Action and Reaction
“Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on
the first.”
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All _______________ act in _______________.
As you _______________ on an object, that _______________ pushes back on _______________.
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The force that you _______________ to the box is _______________ to the amount of force the
_______________ applies back on you, it just acts in the _______________ direction.
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To walk, _______________ exert a _______________ push on the ground (the action force) which causes
the _______________ to push you _______________ (the reaction force).
The _______________ you exert on the _______________ doesn’t cause it to _______________ because
the Earth has a huge amount of _______________ and the force you exert is too _______________ to
move it. Luckily, the force the Earth exerts _______________ on you is enough to _______________ you
forward!
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If you exert a force on your friend’s shoulders while on ice, you will be propelled backwards.
Objects in Motion have Momentum
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_______________is similar to _______________ in that it depends on _______________. However,
momentum also depends on _______________.
o A Ford Explorer has _______________ momentum than a Mini Cooper if they are moving at the
_______________ speed.
o A Hummer going _____ mph has more momentum than a Hummer going ______ mph.
Momentum = Mass x Velocity or (_______________)
Example problems:
1.
What is the momentum of a 1.5 kg ball moving at 2 m/s?
2. What is the momentum of a 2000 kg car moving at 29 m/s ?
3. What is the momentum of a 10,000 kg airplane moving at 322 km/h?
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Momentum is _______________from one object to another during a _______________.
o As two objects collide, the momentum of the _______________ object is transferred to the
_______________ object and the momentum of the _______________ object is transferred to
the _______________ object.
o The _______________ amount of momentum stays the _______________before and after the
collision.
o This is called the _______________ of _______________ and is explained by Newton’s
_______________ Law of Motion (action and reaction forces).