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Physical Science
Name
The Laws of Motion
Date _____/_____/_____ Period _____
Use the given words to fill in the blanks.
Accelerated Motion
Newton’s Second Law
kilogram
same
Newton
increases
larger
net force
The acceleration of an object increases as the amount of
applied to the object
. A small mass will have a greater acceleration than a
mass if the
force is applied to each. One
is the force needed to cause a one
mass to be accelerated
one meter per second each second.
Falling Objects
terminal velocity
acceleration
gravitational
atmosphere
air resistance
moving object
net force
air resistance
increases
second
terminal velocity
9.8 m/sec2
upward
shape
reduces
kilograms
equal
All objects near the surface of Earth fall with the same
. If an object started falling
from rest, it would be traveling 9.8 m/sec at the end of one
accelerates only if it has a
. An object
on it. The force on a
falling object is the
attraction of Earth. To find the weight of an object in
Newtons, multiply its mass in
by the acceleration due to gravity,
. An object falling in Earth’s atmosphere has another force on it called
. Air resistance is the force exerted by air on a
. Air resistance acts in the
the speed, size, and
direction, and depends on
of the falling object. As an object falls in air, the air
resistance
as the speed increases. When the upward force of air against the
object is
to the downward force of gravity, the object no longer accelerates.
The largest velocity reached by a falling object is
. The acceleration of an object on the moon is the same throughout its fall because there is no
. Feathers fall more slowly than heavy, solid
objects because of Earth’s
. An open tissue very quickly reaches
when it falls. The resistance of air on a parachute
the terminal velocity of a falling person.
Projectiles
vertical velocity
horizontal velocity
direction
independent
constant
horizontal
vertical
force of gravity
is parallel to the surface of Earth.
is toward Earth. When objects such as stones, balls, and arrows are
thrown or shot, they have two kinds of motion,
and
When an arrow is shot, the horizontal velocity is
more is exerted in that
.
because once in flight no
. The vertical velocity of the arrow is accelerating
downward because the
. The
vertical and horizontal velocities are completely
of each other.
Motion in Circles
circular motion
centripetal force
force
changing
center
straight line
net force
higher
Any object will continue in a straight-line path unless a
acts
on it. The acceleration of an object moving in a circular path is toward the
of the
circle. In the case of a car rounding a curve, the frictional force of the road on the tires exerts the
. Highways are often built with the outside edge of curves
than the inside edge. This increases the available
toward the center. A
satellite in orbit about Earth is an example of
.
Without gravity, a satellite would continue along in a
, not in a circular path. As a satellite circles Earth, the direction of its motion keeps
.