Gravity: A Force of Attraction

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Transcript Gravity: A Force of Attraction

Name:
Understanding Gravity
 ____________ is the force of attraction between objects
due to their masses.
 The force of gravity can affect the __________ of an object
or the ___________ of the object’s motion.
 All ______________ has mass
 Earth has a huge ___________.
 Earth’s _____________________ pulls everything toward
the center of Earth.
direction
gravity
mass
gravitational force
matter
position
What is Gravity?
Fill in the Blank
 _______________ is the pull towards the center of the Earth.
 Gravity is actually an attractive ___________ that acts between
any ____________ objects.
 The greater the ____________ of an object, the greater its
gravitational _________________.
attraction
force
gravity
mass
two
Check for Understanding
 Name the 2 essential questions people asked for thousands
of years.
 What was the name of the scientist that realized that the
same unbalanced force affected the motions of the apple
and the moon?
 What is the name of the law that describes the relationship
between gravitational force, mass, and distance?
True/False
 Objects of any size exert a gravitational force.
 The moon is held in its orbit by unbalanced forces.
 If you traveled to Jupiter and you neither gained or
lost mass, your weight on Jupiter would be much
greater than your weight on Earth.
Falling Objects
Answer True or False
Newton had ideas about falling objects in the 1500’s.
Two objects that are the same size with different masses will hit
the ground at the same time when dropped.
Objects gain speed at the same rate.
If you drop a sheet of paper and a crumpled paper at the same
time, they hit the ground at the same time.
Objects in a sweeper will fall at the same rate.
Objects that fall toward Earth accelerate at 9.8 m/s.
The Law of Universal Gravitation
Answer the following questions.
 What 2 things does the force of gravity depend on?
 What holds everything on Earth?
 What do all planets in the solar system revolve around?
 The greater the _______ of an object, the greater its
gravitational pull.
Gravity
Fill in the Blank
 _________ is directly related to gravity.
 The gravitational pull on the _________ is _________ than
that on Earth.
 An object dropped on Earth increases its _________ by
9.8m/s/s.
 Weight is equal to mass times ______________.
gravity
less
moon
speed
weight
Weight vs. Mass
Use weight or mass to answer the
questions.
 Is the amount of gravitational pull on an object.
 Is the measure of the amount of matter in an object.
 Is measured by using a balance scale.
 Is measured with a spring scale.
 Is different depending on where it is measure.
 Is never changing no matter where it is measured
QUESTIONS
 Why must you exert a force to pick up an object?
 How does mass affect gravitational force?
 How is gravitational force related to the weight of an
object?
QUESTIONS CONTINUED
 What is the difference between mass and weight?
 What must you know in order to calculate the
gravitational force between two objects?
 Where would you weigh the most, on a boat, on the space
shuttle, or on the moon?
REVIEW
 _________ opposes motion between surfaces that are
touching.
 The _________ is the unit of force.
 _________ is determined by combining forces.
 Acceleration is the rate at which ____________ changes.
 ____________ is a measure of the gravitational force on an
object.
newton
friction
weight
net force
velocity