Download Final Exam Review

Final Exam Review
Chapters 11, 12, 14
Question
• A passenger in the rear seat of a car moving at
a steady speed is at rest relative to:
a)
b)
c)
d)
The side of the road
A pedestrian on the corner ahead
The front seat of the car
The wheels of car
Answer
• C
Question
• What distance can be most accurately
measured with a ruler?
a)
b)
c)
d)
The length of a river
The width of a book
The distance between two cities
The size of an object under a microscope
Answer
• B – the width of a book
Question
• A person drives north 3 blocks, then turns east and drives
3 blocks. The driver then turns south and drives 3 blocks.
How could the driver have made the distance shorter
while maintaining he same displacement?
a) By driving east 3 blocks from the starting point
b) By driving north 1 block and east 4 blocks
c) By driving west 3 blocks from the starting point
d) By driving back to the starting point by the same
route
Answer
• A
Question
• Speed is the ratio of the distance an object
moves to
a) The amount of time needed to travel the
distance
b) The direction the object moves
c) The displacement of the object
d) The motion of the object
Answer
• A
Question
• A car traveled 88 km in 1 hour, 90 km in the
next 2 hours, and then 76 km in 1 hour before
reaching its destination. What was the car’s
average speed?
a)
b)
c)
d)
254 km/h
63.5 km/h
209 km/h
74.5 km/h
Answer
• B
Question
• Vector addition is used when motion involves
a)
b)
c)
d)
More than one distance
More than one velocity
More than one speed
All of the above
Answer
• B
Question
• Which example identifies a change in motion
that produces acceleration?
a) A speed skater moving at a constant speed on a
straight track
b) A ball moving at a constant speed around a
circular track
c) A particle moving in a vacuum at constant
velocity
d) A vehicle moving down the street at a steady
speed
Answer
• B
Question
• An object moving at 30 m/s takes 5 s to come
to a stop. What is the object’s acceleration?
a)
b)
c)
d)
30 m/s2
-30 m/s2
-6 m/s2
6 m/s2
Answer
• C
Question
• A person walks 1 mile every day for exercise,
leaving her front porch at 9:00 A.M. and
returning to her front porch at 9:25 A.M.
What is the total displacement of her daily
walk?
a)
b)
c)
d)
1 mile
0
25 minutes
None of the above
Answer
• 0
Question
• A ball is rolled uphill a distance of 3 meters
before it slows, stops, and begins to roll back.
The ball rolls downhill 6 meters before coming
to rest against a tree. What is the magnitude
of the ball’s displacement?
a)
b)
c)
d)
3 meters
6 meters
9 meters
18 meters
Answer
• A
Question
• Instantaneous speed is measured
a)
b)
c)
d)
At the starting point
When the object reaches its destination
At a particular instant
Over the duration of the trip
Answer
• C
Question
• The slope of a line on a distance-time graph is
a)
b)
c)
d)
Distance
Time
Speed
Displacement
Answer
• C
Question
• The rate at which velocity changes is
a)
b)
c)
d)
Speed
Vectors
Acceleration
Motion
Answer
• C
Question
• Objects in free fall near the surface of the
Earth experience
a)
b)
c)
d)
Constant speed
Constant velocity
Constant acceleration
Constant distance
Answer
• C
Question
• Suppose you increase your walking speed
from 1 m/s to 3 m/s in a period of 2 s. What is
your acceleration?
a)
b)
c)
d)
1 m/s2
2 m/s2
4 m/s2
6 m/s2
Answer
• A
Question
• The slope of a speed-time graph indicates
a)
b)
c)
d)
Direction
Acceleration
Velocity
Speed
Answer
• B
Question
• An object that is accelerating may be
a)
b)
c)
d)
Slowing down
Gaining speed
Changing direction
All of the above
Answer
• D
Question
• Displacement and velocity are examples of
___________________________ because
they have both direction and magnitude.
Answer
• Vectors
Question
• The SI unit for measuring
__________________________ is the meter.
Answer
• Distance
Question
• A car’s speedometer measures
_______________________________.
Answer
• Instantaneous Speed
Question
• Freely falling objects accelerate at 9.8 m/s2
because the force of
__________________________ acts on them.
Answer
• Gravity
Question
• Which is not a force?
a)
b)
c)
d)
friction
Gravity
Momentum
weight
Answer
• C - momentum
Question
• You push on a box and are unable to move it.
What force opposes your push?
a)
b)
c)
d)
Static friction
Rolling friction
Sliding friction
Air resistance
Answer
• A – static friction
Question
• Air resistance depends on
a)
b)
c)
d)
The velocity of a moving object
The weight of a moving object
The mass of a moving object
The inertia of a moving object
Answer
• A – the velocity of a moving object
Question
• What force besides gravity acts on a
projectile?
a)
b)
c)
d)
Weak nuclear
Electrical
Magnetic
Air resistance
Answer
• D – air resistance
Question
• Newton’s first law of motion is sometimes
called the law of
a)
b)
c)
d)
Inertia
Conservation
Momentum
resistance
Answer
• A - inertia
Question
• A change of which of the following affects the
weight of an object?
a)
b)
c)
d)
Momentum
Velocity
Acceleration due to gravity
friction
Answer
• C – acceleration due to gravity
Question
• Which represents Newton’s second law?
a)
b)
c)
d)
V = d/t
A = F/m
F = mv
F=0
Answer
• B – a = F/m
Question
• For every action force there is a
a)
b)
c)
d)
Reaction force
Net force
Friction force
Unbalanced force
Answer
• A – reaction force
Question
• Momentum depends upon
a)
b)
c)
d)
Force only
Velocity and friction
Weight and mass
Mass and velocity
Answer
• D - Mass and velocity
Question
• What force holds the nucleus together?
Answer
• Strong nuclear
Question
• What happens to an object when an
unbalanced force acts on it?
Answer
• It moves/accelerates
Question
• You push harder and harder on a box until it
begins sliding across the floor. Which was the
stronger of the forces acting on the box, static
or sliding friction?
Answer
• static
Question
• What is the difference between mass and
weight?
Answer
• Weight depends on gravity whereas mass
doesn’t
Question
• What force is responsible for your socks
sticking together after they have been in the
clothes dryer?
Answer
• Electromagnetic force
Question
• What force is responsible for the orbits of the
planets in the solar system?
Answer
• Gravity/centripetal force
Question
• When a tennis player practices by hitting a ball
against a wall, which of Newton’s laws of
motion is the player making use of?
Answer
• N3L
Question
• What are 2 ways in which the acceleration of
an object can be increased? (1 point each)
Answer
• Decrease mass or increase force
Question
• Which statement about an object falling at
terminal velocity is true?
a)
b)
c)
d)
e)
Unbalanced forces act on the object
The net force acting on the object is zero
The object is accelerating
The object is traveling in a circular path
No fluid friction acts on the object
Answer
• B
Question
• Which has the greatest momentum?
a)
b)
c)
d)
e)
A huge boulder at rest
A small pebble that is tossed into the air
A baseball after it is hit with a bat
A small pebble at rest
A car traveling on a highway
Answer
• e
Question
• Projectile motion is caused by
a) The downward force of gravity
b) An initial forward velocity
c) The downward force of gravity and an initial
forward velocity
d) A final vertical velocity
Answer
• C
Question
• When opposite poles of two magnets are
brought together, the poles ___________
each other.
Answer
• Attract
Question
• The SI unit of force is the
Answer
• Newton
Question
• A push or a pull is an example of a(n)
______________.
Answer
• force
Question
A force acting on an object does no work if
a. a machine is used to move the object.
b. the force is not in the direction of the object’s
motion.
c. the force is greater than the force of friction.
d. the object accelerates
Answer
• b
Question
If you exert a force of 10.0 N to lift a box a
distance of 0.75 m, how much work do you do?
Don’t forget units!
Answer
• 7.5 J
Question
If you exert a force of 500 N to walk 4 m up a
flight of stairs in 4 s, how much power do you
use?
Answer
• 500 W
Question
Which of the following statements is true?
a. To increase power, you can decrease the amount of work
you do in a given amount of time, or you can do a given
amount of work in less time.
b. To increase power, you can decrease the amount of work
you do in a given amount of time, or you can do a given
amount of work in more time.
c. To increase power, you can increase the amount of work
you do in a given amount of time, or you can do a given
amount of work in less time.
d. To increase power, you can increase the amount of work
you do in a given amount of time, or you can do a given
amount of work in more time.
Answer
• c
Question
A 750-W motor might also be rated as a
a. 0.5-horsepower motor.
b. 1-horsepower motor.
c. 2-horsepower motor.
d. 10-horsepower motor.
Answer
• B
Question
When a machine does work, it can do all of the
following EXCEPT
a. change the direction of a force.
b. increase a force and change the distance a
force moves.
c. increase the distance a force moves and
change the
direction of a force.
d. increase a force and increase the distance a
Answer
• D
Question
If you know the input distance and output
distance of a machine, which of the following
can you calculate?
a. work
b. actual mechanical advantage
c. efficiency
d. ideal mechanical advantage
Answer
• D
Question
A 100-m long ski lift carries skiers from a station
at the foot of a slope to a second station 40 m
above. What is the IMA of the lift?
Answer
• 2.5
Question
The efficiency of a machine is always less than
100 percent because
a. a machine cannot have an IMA greater than 1.
b. some work input is lost to friction.
c. the work input is too small.
d. the work output is too great.
Answer
• B
Question
A motor with an efficiency rating of 80 percent
must supply 300 J of useful work. What amount
of work must be supplied to the motor?
Answer
• 375 J
Question
• What is the SI unit of work?
Answer
• joule
Question
The actual mechanical advantage of a machine
a. cannot be less than 1.
b. decreases as the input distance increases.
c. increases with greater friction.
d. is less than the ideal mechanical advantage of
the machine.
Answer
• D
Question
If you have to apply 30 N of force on a crowbar
to lift an rock that weights 330 N, what is the
actual mechanical advantage of the crowbar?
Answer
• 11
Question
A mechanical device requires 400 J of work to
do 340 J of work in lifting a crate. What is the
efficiency of the device?
Answer
• 85%
Question
An inclined plane reduces the effort force by
a. increasing the distance through which the
force is applied.
b. increasing the work.
c. reducing the effort distance.
d. reducing the work
Answer
• A
Question
• An ax is an example of a(n)
_____________________.
Answer
• wedge
Question
An example of a compound machine is a
a. crowbar.
b. bicycle.
c. ramp.
d. seesaw.
Answer
• B
Question
• The ________________ of a machine is the
number of times that the machine increases
the input force.
Answer
• Mechanical Advantage
Question
• A ___________________ can be described as
an inclined plane wrapped around a wedge.
Answer
• screw
Question
The ideal mechanical advantage of a third class
lever is always ________________ 1.
a. Greater than
b. Less than
c. Equal to
Answer
• B