Chapter 2 Study Guide
Answers
Question 1
What two things
are needed to
describe a
vector.
 Direction and magnitude
 Remember, force is a
vector. Force has a direction
(we show it with arrows),
and the magnitude is the
strength of the force (we
measure it in Newtons. The
larger the force, the longer
the arrow).
Question 2
Describe
magnitude in
two different
ways.
 Size or measurement
 10 degrees
 50 yards
 20 m/s2
 25 newtons (Force!)
 Magnitude is something
you can masure.
Question 3
Give two
examples of
units for a force.
 200 newtons left
 66 newtons south
 2 m/s2 south
 Recall force is a vector
and all vectors need
direction and magnitude
Question 4
Identify all of the  Gravity
types of forces
 Normal
acting as you sit  Applied
in your chair.
 Balanced
Question 5
Identify all of the
types of forces
acting on
another object
that is moving.
 Gravity
 Normal
 Friction
 Inertia - maybe
 If the speed is constant
and traveling in a
straight line it is
balanced.
Question 6
What happens
where forces are
balanced?
 Net force is zero
 Motion doesn’t change
 But it can be moving, just at a
constant speed and direction.
 Recall: velocity changes when
an object speeds up, slows
down or changes direction. If
velocity changes, the forces are
UNBALANCED. This is why
forces are BALANCED at a
constant speed.
Question 7
Give two
examples of
balanced forces.
 Share out your
examples.
 A car with cruise
control on. (Constant
speed).
 An object at rest.
Question 8
What happens
when forces are
unbalanced.
 Net force is NOT zero
 Velocity will change
therefore acceleration is
changing.
 Slowing down
 Speeding up
 Changing direction
Question 9
Give two
examples of
unbalanced
forces.
 Share out your
examples.
Question 9
Give two
examples of
unbalanced
forces.
 Share out your
examples.
 One team wins a game
of tug-o-war
 Any object that is
changing velocity
Question 10
 Decrease mass
Describe two ways to  Increase force
increase the
magnitude of an
 For example, how can
object’s acceleration.
she increase
acceleration?
 Reduce the amount of
weights.
 Increase force by
strengthening her muscles
Question 11
Put the law of
universal
gravitation in
your words and
give an example.
 All objects are pulled towards
each other by gravity. The force
of this pull is affected by the
size of the two objects and/or
the distance between them.
 Example (pg 97): Earth is large
enough and close enough to
exert force on us (Gravity pulls
from Earth’s core).
 As Mass increases, Gravity
increases (and vice versa)
 As distance increases, gravity
decreses (and vice versa).