Download Sample Exam 3

SAMPLE EXAM 3
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PHYS1013/1014
Spring 2014
Prof. K. Tapp
Give the fundamental physics unit in the system specified.
a)
___________________ SI unit of length
b)
___________________ British unit of length
c)
___________________ SI unit of time
Give the prefix for each power-of-10 multiple.
a)
___________________106
___________________10-2
b)
3.
Convert 60 mph to km/s if
1 mile = 1.6 km, 1 hour = 60 min, 1 min = 60 s
4.
Define a vector and a scalar quantity.
5.
A runner travelling at a constant speed runs 105 m in 15 s. (a) What is the runner's
average speed? (b) How far will the runner go in 20 s?
6.
If the Sun is a distance of 1.5 x 108 km from the Earth, how long, in minutes, does it take
sunlight to reach the Earth if it moves at a constant speed of 3 x 108 m/s?
7.
An object is observed to fall from a bridge, striking the water below 2.50 s later. (a) With
what velocity did it strike the water? (b) How high is the bridge?
8.
At a recent performance of “Peter Pan” in the OCCC Performing Arts Theater, stage
crews were able to make the lead actor fly on stage with the help of a pulley system.
Assuming an actor (mass = 75 kg) is lifted at a constant rate using a single frictionless
pulley, with how much force is the stage crews pulling on the cable?
9.
State the Law of Conservation of Linear Momentum.
10.
An automobile (m = 1500kg) moving at 24 m/s collides inelastically with a truck (m =
3000kg) traveling at 10 m/s in the same direction. Find the velocity of the two-vehicle
combination immediately after the collision.
11.
In a human centrifuge used for astronaut training, a pilot blacked out when his linear
velocity was 13.5 m/s. If he was traveling in a circle of radius 3.0 m, determine the
centripetal acceleration at blackout.
12.
State Newton’s 3 Laws of Motion.
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Multiple Choice Questions:
1.
An object is pulled northward with a force of 10 N and southward with a force of 15 N.
The magnitude of the net force on the object is
a. 0 N
b. 5 N
c. 10 N
d. 15 N
e. none of the above
2.
Whenever the net force on an object is zero, its acceleration
a. may be zero.
b. is zero.
3.
The two measurements necessary for calculating average speed are
a. acceleration and time.
b. velocity and time.
c. distance and time.
d. distance and acceleration.
e. displacement and time.
4.
As an object freely falls, its
a. velocity increases.
c. both of the above.
b. acceleration increases.
d. none of the above.
5.
The gain in speed each second for a freely falling object is about
a. 0.
b. 5 m/s.
c. 10 m/s.
d. 20 m/s.
e. depends on the initial speed.
6.
A force is a vector quantity because it has both
a. magnitude and direction.
b. mass and acceleration.
c. action and reaction counterparts.
7.
Which of the following will be identical on Earth and on the Moon?
a. the weight of a rock
b. the mass of a rock
8.
According to Newton’s first law of motion, which of the following must have a net force
of zero?
a. A man pushing a box across a floor.
b. A bullet as it leaves the barrel of a gun.
c. A hotel porter carrying suitcases up a flight of stairs.
d. A horse running at a constant speed in a straight line path.
9.
A man pushes on a wall with a force of 10 N.
a. The action is a 10 N force on the wall.
b. The action is a 10 N force on the man.
c. Either (a) or (b) could be correct.
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13.
Momentum is conserved in …
a. most collisions.
b. no collisions.
c. all collisions.
The meter is the standard unit of …
a. time.
b. length.
c. resistance.
One meter is equal to …
a. 39.3701 inches.
c. answers a & b.
The metric system uses …
a. meter, kilopounds, second
c. meter, kilogram, second
d. force.
b. a little more than a yard
d. none of the above.
b. meter, pound, second
d. inch, ounce, hour
14.
1000 meters equals _________ kilometers.
a. 10
b. 1
c. 100
d. 2
15.
Your weight is
a. actually your mass.
b. the gravitational attraction between you and Earth.
c. a property of mechanical equilibrium.
d. the same in all locations.
16.
A 300-kg bear grasping a vertical tree slides down at constant velocity. The friction force
between the tree and the bear is approximately
a. 30 N
b. 300 N
c. 3000 N
d. more than 3000 N
17.
Which force remains constant when an object falls?
a. gravity
b. air resistance.
c. They both are constant.
18.
A golfer hits a golf ball. If the action is: golf club hits ball, what’s the reaction?
a. Ball hits golf club.
b. Ball hits tree.
c. Ball hits golfer.
19.
A package falls off a truck that is moving at 30 m/s. Neglecting air resistance, the
horizontal speed of the package just before it hits the ground is
a. zero.
b. less than 30 m/s, but larger than zero.
c. about 30 m/s.
d. more information needed for an estimate.
20.
What is the acceleration of a car that maintains a constant velocity of 100 km/h for 10 s?
a. 0 m/s2
b. 10 km/h/s
c. 10 m/s2
d. 1000 km/h/s
21.
A car accelerates from rest at 2 m/s2. What is its speed 3 s after the car starts moving?
a. 2 m/s
b. 3 m/s
c. 4 m/s
d. 6 m/s
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22.
An object is propelled along a straight-line path by a force. If the net force were doubled,
its acceleration would
a. quadruple. b. double.
c. stay the same.
d. halve.
e. none of these.
23.
Disregarding air resistance, objects fall at constant
a. velocity.
b. speed.
c. acceleration.
d. distances.
24.
A bullet is dropped into a river from a very high bridge. At the same time, another bullet
is fired from a gun, straight down towards the water. Neglecting air resistance, the
acceleration just before striking the water
a. is greater for the dopped bullet.
b. is greater for the fired bullet.
c. is the same for each bullet.
d. depends on how high they started.
25.
A heavy block at rest is suspended by a vertical rope. When the block is accelerated
upward by the rope, the rope tension
a. increases.
b. decreases.
c. remains the same.
26.
If you drop an object, it will accelerate downward at a rate of about 10 m/s2. If you
instead throw it downwards, its acceleration (in the absence of air resistance) will be
a. less than 10 m/s2.
b. 10 m/s2.
c. greater than 10 m/s2.
27.
A player catches a ball. Consider the action force to be the impact of the ball against the
player's glove. The reaction to this force is the
a. air resistance on the ball.
b. force the glove exerts on the ball.
c. friction of the ground against the player’s shoes.
d. muscular effort in the player’s arms.
e. none of these.
28.
Which of the following has the largest momentum relative to the Earth?
a. a tightrope walker crossing Niagara Falls
b. a pickup truck speeding along a highway
c. a Mack truck parked in a parking lot
d. swimming pool on OCCC’s campus
e. a dog running down the street
29.
A ball is moving at 4 m/s and has a momentum of 48 kg·m/s. What is the ball's mass?
a. 4 kg
b. 12 kg
c. 48 kg
d. 192 kg
e. 0 kg
30.
You're driving down the highway and a bug spatters into your windshield. Which
undergoes the greater change in momentum?
a. the bug
b. your car
c. both the same
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31.
Ten seconds after being dropped from the top of Seattle’s Space Needle, a freely falling
penny will have a speed of about
a. 10 m/s.
b. 50 m/s.
c. 100 m/s.
d. 250 m/s.
32.
An apple falls from a tree and hits the ground 5 m below. It hits the ground with a speed
of about
a. 5 m/s.
b. 10 m/s.
c. 15 m/s
d. 20 m/s.
33.
It takes 6 s for a stone to fall to the bottom of a mine shaft. How deep is the shaft?
a. about 60 m
b. about 120 m
c. about 180 m
d. more than 200 m
34.
Consider drops of water that leak from a dripping faucet. As the drops fall, they
a. get closer together.
b. get farther apart.
c. remain at a relatively fixed distance from one another.
35.
Drop a rock from a 5-m height and it accelerates at 10 m/s/s and strikes the ground 1 s
later. Drop the same rock from a height of 2.5 m and its acceleration of fall is
a. about half.
b. the same.
c. more.
36.
A girl pulls on a 10-kg wagon with a constant force of 30 N. What is the wagon's
acceleration in meters per second per second?
a. 0.3
b. 3.0
c. 10
d. 30
37.
Suppose you're coasting in a car at 60 km/h and apply the brakes until you slow to 40
km/h. When you suddenly release the brake, the car tends to
a. momentarily regain its higher initial speed.
b. continue moving at 40 km/h in the absence of forces.
c. decrease in speed whether or not other forces act.
38.
An archer shoots an arrow. Consider the action force to be the bowstring against the
arrow. The reaction to this force is the
a. weight of the arrow.
b. air resistance against the bow.
c. friction of the ground against the archer’s feet.
d. grip of the archer’s hand on the bow.
e. arrow’s push against the bowstring.
39.
A player hits a ball with a bat. The action force is the impact of the bat against the ball.
The reaction to this force is the
a. air resistance on the ball.
b. weight of the ball.
c. force of the ball against the bat.
d. grip of the player’s hand against the ball.
40.
A piece of rope is pulled by two people in a tug-of-war. Each pulls with 400 N of force.
What is the tension in the rope?
a. 0 N
b. 400 N
c. 600 N
d. 800 N
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41.
Your friend says that the heavyweight champion of the world cannot exert a force of 50
N on a piece of tissue paper with his best punch. The tissue paper is held in midair, no
wall, no tricks. You
a. agree that it can’t be done.
b. have reservations about this assertion.
c. disagree, for a good punch easily delivers this much force.
42.
A 60 vibration per second wave travels 30 m in 1 s. Its frequency is
a. 30 Hz and it travels at 60 m/s.
b. 60 Hz and it travels at 30 m/s.
43.
How many vibrations per second are associated with a 101-MHz radio wave?
a. less than 101,000,000
b. 101,000,000
c. more than 101,000,000
44.
A wave travels an average distance of 6 m in 1 s. What is the wave's velocity?
a. less than 0.2 m/s
b. 1 m/s
c. 3 m/s
d. 6 m/s
45.
You dip your finger repeatedly into water and make waves. If you dip your finger more
frequently, the wavelength of the waves
a. shortens
b. lengthens
c. stays the same
46.
During a single period, the distance traveled by a wave is
a. one-half wavelength
b. one wavelength
47.
The vibrations of a longitudinal wave move in a direction
a. along the direction of wave travel
b. at right angles to the direction of wave travel
48.
The vibrations of a transverse wave move in a direction
a. along the direction of wave travel
b. at right angles to the direction of wave travel
49.
A sound wave is a
a. longitudinal wave b. transverse wave
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c. two wavelengths
c. standing wave
The range of human hearing is from about
a. 10 Hz - 10,000 Hz
b. 20 Hz - 20,000 Hz
d. shock wave
c. 40 Hz - 40,000 Hz
We are best at hearing
a. infrasonic sound. b. ultrasonic sound. c. both of these
d. none of these
The speed of a sound wave in air depends on
a. its frequency
b. its wavelength
c. air temperature
d. none of these
Sound travels faster in air if the air is
a. warm.
b. cold.
c. neither warm nor cold.
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54.
An explosion occurs 34 km away. Knowing that sound travels at 340 m/s, the time it
takes for the sound to reach you is
a. 0.1 s
b. 1 s
c. 10 s
d. 20 s
e. more than 20 s
55.
In designing a music hall, an acoustical engineer deals mainly with
a. modulation b. resonance c. beats
d. wave interference
56.
Sound waves can interfere with one another so that no sound results.
a. True
b. False
57.
A Doppler effect occurs when a source of sound moves
a. toward you.
b. away from you. c. both of these.
d. none of these
For light, a red shift indicates the light source moves
a. toward you.
b. away from you. c. at right angles.
d. none of these.
For light, a blue shift indicates the light source moves
a. toward you.
b. away from you. c. at right angles.
d. none of these.
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The sky is blue because air molecules in the sky act as
a. mirrors that reflect only blue light.
c. resonators that scatter & disperse blue light.
END OF SAMPLE EXAM
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b. sources of white light.
d. prisms.