Download Q: Who established the law of universal gravitation? Q: What is a

Q: Who established the law of universal
gravitation?
A: Newton
Q: What is a spring scale used for?
A: To measure weight
Q: What is the Law of Universal Gravitation?
A: Everything in the universe has gravity.
Q: What is mass?
A: Mass is the amount of matter in an object
Q: What is weight?
A: Weight is a measurement of the force of
gravity on an object.
Q: Why do astronauts on the moon seem to
bounce around so effortlessly?
A: The moon has 1/6th the amount of gravity
that the Earth has.
Q: What two factors determine the amount of
gravitational attraction between two objects?
A: The mass of an object and the distance
between two objects.
Q: What will happen on Earth if you drop a
hammer and a feather at the same time and
from the same height? Why?
A: The hammer will land first because air
resistance has a larger affect on the feather
causing it to slow down as it falls.
Q: What will happen on the Moon if you drop a
hammer and a feather at the same time and
from the same height? Why?
A: They will land at the same time. The moon
doesn’t have an atmosphere – so neither
object is affected by air resistance.
Q: Would your weight be the same at the base
of a mountain and at the top of the same
mountain? Explain.
A: At the top of the mountain you would weigh
a little bit less than at the base of the same
mountain. This is because at the top of the
mountain you are farther away from the center
of the Earth.
Q: How can we tell if an object is moving?
A: Motion is always observable as a change in
an object’s position compared to objects that
are still, or not moving.
Q: How do you calculate speed?
A: Distance divided by time
Q: What is velocity?
A: Velocity is the speed of an object in a
particular direction.
Q: True or False? Two objects traveling at the
same velocity stay in the same position relative
to each other.
A: True
Q: What happens to the velocity of an object
moving in a circle, like a planet orbiting around
a star?
A: The velocity of an object moving in a circle
is constantly changing, because the direction
of the movement is constantly changing.
Q: What changes an objects velocity?
A: A force.
Q: What are two factors that affect
momentum?
A: how much mass an object has and its
velocity (how fast it is going and in what
direction)
Q: How is it possible for two objects traveling
the same speed to have different velocities?
A: they are traveling in different directions
Q: How is it possible for two objects traveling in
the same direction to have different velocities?
A: the have different speeds
Q: What is Newton’s 1st Law of Motion?
A: An object at rest will remain at rest, and an
object in motion will remain in motion in a
straight line unless a force acts on the object.
Q: Objects tend to keep on doing what they are
currently doing unless what acts on them to
change this condition?
A: A force
Q: What do you call the resistance of an object
to a change in motion?
A: inertia. Remember even objects at rest
have inertia.
Q: What is the other name for Newton’s 1st Law
of Motion?
A: The Law of Inertia
Q: What two forces often act on objects
causing them to slow down and stop?
A: gravity and friction
Q: A substance that decreases friction is called
a ______________.
A: lubricant (example: oil)
Q: What property of objects makes them tend
to resist a change in motion?
A: Inertia
Q: What is an unbalanced force?
A: An unbalanced force is a force without an
equal force in the opposite direction.
Q: What changes when an unbalance force
acts on an object?
A: when an unbalanced force acts on an
object, it changes the velocity of the object (its
speed, its direction, or both).
Q: What is acceleration?
A: Acceleration is the rate of change in velocity
of an object.
Q: What two properties affect acceleration of
an object?
A: the size of the force and the mass of the
object
Q: Fill in the blank. The greater the force, the
_____ is the acceleration, or change in
velocity.
A: The greater the force, the greater is the
acceleration, or change in velocity.
Q: Fill in the blank. The greater the mass, the
______ is the acceleration, or change in
velocity.
A: The greater the mass, the smaller is the
acceleration, or change in velocity.
Q: Do heavier objects require more or less
force to move the same distance as lighter
objects?
A: They require more force.
Q: If I push an object north, what direction will it
go?
A: North
Q: If I push two objects with the same amount
of force and in the same direction which will
move the fastest?
A: The lighter object will move the fastest.
Q: why are heavier objects harder to stop and
start than lighter objects?
A: Because they have more mass.
Q: What is the equation for force that we use
when we discuss Newton’s 2nd Law of Motion?
A: Force = mass x acceleration
Q: What unit do we use for force?
A: N (Newton)
Q: What is Newton’s 3rd Law of Motion?
A: For every action force there is an equal and
opposite reaction force.
Q: True or False? Forces never come in pairs.
A: False! Forces always come in pairs!
Q: What is true about action and reaction
forces?
A: Action and reaction forces are always equal
in size and opposite in direction.
Q: Why does an object accelerate as it falls?
A: The acceleration of a falling object is due to
the force of gravity.
Q: What happens when forces are balanced?
A: Nothing moves
Q: What happens to the balance between
gravitational potential energy and mechanical
kinetic energy as you start a pendulum
moving?
Q: The pendulum will have the most
gravitational potential energy and the least
mechanical kinetic energy just before it is
released. It will have the most mechanical
kinetic energy and the least amount of
gravitational potential energy at the bottom on
its swing. This is a gradual change between
these two forms of energy.
Q: What is the measure of the total distance an
object has moved divided by the total elapsed
time called?
A: Average speed
Q: Why is the velocity of an object moving in a
circle constantly changing?
A: Velocity is speed in any given direction. The
velocity of an object moving in a circle is
constantly changing because the direction of
movement is constantly changing.
Q: If you slide an object to the east, in what
direction does the force of friction act to resist
the motion?
A: the force of friction is to the west (opposite
the original force).
Q: What is a hypothesis?
A: It is an educated prediction scientists make
before doing an experiment.