Download Balanced Forces

Newton’s Laws Notes Name:_____________________ Date_____________ Period_______________P a g e
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 What ____________________ things to move the way they do?

 Forces
 Force—a ____________________or ____________________that one body
____________________on another

 Balanced Forces
 Net Force—when ____________________or more forces act on an object at the
____________________time
 Balanced Forces—forces that are ____________________in size and
____________________in direction.
– An object will ____________________ ____________________
 Unbalanced Forces
 Unbalanced Forces—The ____________________and ____________________of forces
acting on an object are ____________________.
– cause objects to ____________________.
 Balanced & Unbalanced Forces
Newton’s Laws Notes Name:_____________________ Date_____________ Period_______________P a g e
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 Inertia
 Inertia—the ____________________of an object to resist a ____________________in
its motion
– ____________________of an object only changes if a
____________________changes it.
 The ____________________of an object is related to ____________________
– The ____________________the mass, the greater its ____________________.
 Newton’s 1st Law of Motion
 Newton’s 1st Law: The Law of Inertia
– An ____________________at rest ____________________at rest and an object
in motion stays in ____________________with the same speed and direction
unless acted on by an ____________________force.
 What Galileo did:
 Galileo's Experiment
 The ball would roll ____________________…..
Like in space
 Newton’s 1st Law of ____________________
 Punkin Chunkin: Inertia II
 Why did they call the pumpkin thrower Inertia II?

 Units
 The SI unit for ____________________=kilogram (kg)
 The unit for ____________________= meters per second squared (m/s2)
 So the unit for ____________________= kg x m/s2
 The kg x m/s2 is called the newton (N)
Newton’s Laws Notes Name:_____________________ Date_____________ Period_______________P a g e
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 Tugboat Problems
 Two tugboats are moving a barge. Tugboat A exerts a force of 3000 Newtons on the
barge. Tugboat B exerts a force of 5000 Newtons in the same direction. What is the
combined force on the barge? Draw arrows showing the individual and combined forces
of the tugboats.
 Tug Boat Questions
 Now suppose that Tugboat C exerts a force of 2000 Newtons on the barge and Tugboat
D exerts a force of 4000 Newtons in the opposite direction. What is the combined force
on the barge? Draw arrows showing the individual and combined forces of the tugboats.
 Friction
 Friction: A force that ____________________motion between
____________________surfaces that are ____________________each other
 The ____________________of friction is dependant upon
– ____________________
– Force pressing the surfaces ____________________
 Types of Friction
 Static Friction
– Friction ____________________two objects that are NOT
____________________. Ex: ____________________
 Sliding Friction
– Friction between two surfaces moving ____________________each other.
– Example: ____________________
Newton’s Laws Notes Name:_____________________ Date_____________ Period_______________P a g e
 Rolling Friction
– Friction between a ____________________object & the surface it is rolling on.
– Ex: ____________________
 Fluid Friction
– Friction between an object and a ____________________or
____________________
– Ex: ____________________
 Air Resistance
 Air Resistance: ____________________of the object's leading surface with air
____________________.
 Dependent upon a variety of factors, most importantly
– the speed of the ____________________
 Increased speeds = ____________________air resistance.
– the cross-sectional ____________________of the object
 Increased cross-sectional area=____________________air resistance
 Newton’s Second Law
 Newton’s 2nd Law: The ____________________of an object is dependent upon the
force acting upon the ____________________and the mass of the object.
 Newton’s ____________________Law as an equation:
F=m×a
 F = force (N)
Newton is the SI Unit of force
 m = mass (kg)
N = kg m / s2
 a = ____________________ (m/s/s)
 Gravity
 Universal law of Gravity:
– Any ____________________objects will exert an ____________________force
on each ____________________
– The size of the force is ____________________on 2 things
 ____________________of both objects
 ____________________between the objects
– The range of gravity never ____________________
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Newton’s Laws Notes Name:_____________________ Date_____________ Period_______________P a g e
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 Therefore it is not ____________________for an object with mass to be
weightless.
 Weight vs. Mass
– Weight: Force of ____________________pulling you toward the earth
– F = ma becomes W = mg
– Weight = mass × gravitational ____________________
 g on Earth is 9.8m/s2
– SI Unit = ____________________
– Weight can ____________________with a change in ____________________.
– Mass: A measure of how much ____________________ an object has
– You know an object has mass because it has ____________________
– SI Unit = ____________________
 Centripetal Force
 Centripetal Force: The ____________________exerted toward the center of a curved
path.
 Earth’s gravity exerts a centripetal force on the Moon that keeps it in a nearly
___________________orbit.
 Falling Objects on Earth
 Near Earth’s surface
acceleration due to gravity is 9.8 m/s2
 If 2 objects with different masses are dropped from the same height, which would
hit the ground first? ____________________
 Projectile Motion
 Anything dropped, thrown, or shot through the air is a ____________________
 Because of gravity and inertia, you can get a ____________________path.
 Monkey and the Zookeeper
 NEWTON’S 3rd LAW:
For every ____________________, there is an equal and
____________________reaction
 “Action” and “Reaction” are names of forces
 Forces ALWAYS occur in ____________________
 Single forces ____________________happen

Newton’s Laws Notes Name:_____________________ Date_____________ Period_______________P a g e
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 “Equal & Opposite”
 In Newton’s 3rd Law, “____________________” means:
 Equal in ____________________, Equal in ____________________.
 occur at EXACTLY the same ____________________.
 In Newton’s 3rd Law, “____________________” means:
 Opposite in direction
 forces are EXACTLY 180o apart in ____________________.
 Writing Action Reaction Forces


 Momentum:
 A property of how much ____________________is required to change the object’s
motion
– The object’s ____________________times its ____________________
 p = mv
– p = momentum
– m = mass
– v = velocity
 SI UNIT = Kg m / s
 Law of Conservation of ____________________
 Momentum may be ____________________to another object
 The total momentum ____________________a collision is ____________________to
the total momentum after the ____________________
 m1v1 = m2v2
 Types of Collisions
 ____________________collisions
– the total ____________________energy before the collision is equal to the total
kinetic energy after the collision.
– Usually the objects ____________________off of each other.
 ____________________collisions
– the total kinetic energy before the ____________________is NOT equal to the
total kinetic energy after the collision.
– Usually the objects stick ____________________