makeup Exam 1
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) How many nanoseconds does it take for a computer to perform one calculation if it performs
calculations
6.7 × 107 ?
second
A) 65 ns
2) What is B) 67 ns
C) 11 ns
D) 15 ns
0.674
to the proper number of significant figures?
0.74
A) 0.91
B) 0.9
C) 0.9108
1)
2)
D) 0.911
3) A car accelerates from 5.0 m/s to 21 m/s at a rate of 3.0 m/s2 . How far does it travel while
accelerating?
A) 207 m
B) 41 m
C) 69 m
D) 117 m
3)
4) A car is travelling north at 17.7 m/s. After 12 s its velocity is 14.1 m/s in the same direction. Find
the magnitude and direction of the carʹs average acceleration.
A) 0.30 m/s2 , North
B) 2.7 m/s2 , North
4)
C) 2.7 m/s2 , South
D) 0.30 m/s2 , South
5) A rescue plane spots a survivor 132 m directly below and releases an emergency kit with a
parachute. If the package descends at a constant vertical acceleration of 6.89 m/s2 and the initial
5)
plane horizontal speed was 68.9 m/s, how far away from the survivor will it hit the waves?
C) 301 m
D) 426 m
A) 446 m
B) 2.64 km
6) A package is dropped from a helicopter moving upward at 15 m/s. If it takes 16.0 s before the
package strikes the ground, how high above the ground was the package when it was released?
(Disregard air resistance.)
A) 1500 m
B) 810 m
C) 1200 m
D) 1000 m
6)
7) The components of vectors B and C are given as follows:
7)
Bx = -9.2
By = -6.1
Cx = -4.5
Cy = +4.3
The angle (less than 180 degrees) between vectors B and C , in degrees, is closest to:
A) 77
B) 84
C) 170
D) 103
E) 10
8) A boy throws a rock with an initial velocity of 3.13 m/s at 30.0° above the horizontal. How long
does it take for the rock to reach the maximum height of its trajectory?
A) 0.313 s
B) 0.282 s
C) 0.160 s
D) 0.441 s
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8)
9) The figure shows an acceleration-versus-force graph for a 125 g object. What should be the value
of the first tick-mark on the vertical scale?
A) 4
B) 0.00800
C) 0.00400
9)
D) 8
10) The figure shows two forces acting on an object, with magnitudes F1 = 78 N and F2 = 26 N. What
10)
third force will cause the object to be in equilibrium?
A) 52 N pointing down
C) 82 N pointing down
B) 82 N pointing up
D) 52 N pointing up
11) What is the maximum distance we can shoot a dart, provided our toy dart gun gives a maximum
initial velocity of 2.78 m/s?
A) 1.39 m
B) 0.79 m
C) 1.58 m
D) More information needed
11)
12) A Ferrari accelerates from 0 to 100.0 km/h in 4.80 s. What force (in Newtons) does a passenger of
mass 68.0 kg experience during acceleration?
A) 82.0 N
B) 342 N
C) 394 N
D) 311 N
12)
13) Bob and Biff throw identical rocks off a tall building at the same time. Bob throws his rock straight
downward. Biff throws his rock downward and outward such that the angle between the initial
velocity of the rock and the horizon is 30 degrees. Biff throws the rock with a speed twice that of
Bobʹs rock. Which rock hits the ground first (assume the ground near the building is flat)?
A) Biffʹs rock
B) They hit at the same time.
C) Bobʹs rock
D) Impossible to determine
13)
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SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
14) Newtonʹs Third Law suggests that a book sitting on a flat table experiences an upward
force due to the table. If this is true, why doesnʹt the book start moving upward?
14)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
15) A ball is thrown vertically upward, reaches a highest point, and comes back down. At the top of its
path, what forces, if any, act on the ball? Explain your answer.
A) no forces
B) only an upward force
C) only a downward force
D) an upward and a downward force, opposing and equal
15)
16) A person gives a shopping cart an initial push along a horizontal floor to get it moving, and then
lets go. The cart travels forward along the floor, gradually slowing as it moves. Consider the
horizontal force(s) on the cart while it is moving forward and slowing. Which of the following
statements is correct?
A) Only a forward force is acting, which diminishes with time.
B) Both a forward and a backward force are acting on the cart, but the backward force is larger.
C) Only a backward force is acting, no forward force.
D) Both a forward and a backward force are acting on the cart, but the forward force is larger.
16)
17) Suppose you are playing hockey on a new-age ice surface in which there is no friction between the
ice and the hockey puck. You wind up and hit the puck as hard as you can. Just after the puck
loses contact with your stick, the puck
A) will start to slow down.
B) will speed up a little, and then move at a constant speed.
C) will not slow down or speed up.
D) will speed up a little, and then slow down.
17)
18) A skydiver reaches a ʺterminal velocityʺ of 120 km/h. If the skydiver has a mass of 59.0 kg, what is
the magnitude of the upward force on the skydiver due to wind resistance? (Use g = 9.8 m/s2 .)
18)
A) 578 N
B) 6.02 N
C) 636 N
D) 5.42 N
19) An object at rest on an inclined plane starts to slide when the incline angle is increased to 17°. What
is the coefficient of static friction between the object and the incline? (Use g = 9.8 m/s2 .)
A) 0.27
B) 0.31
C) 0.37
D) 0.33
20) If you were to move into outer space far from any stars or planets,
A) both your weight and mass would change.
B) your weight would change, but your mass would not change.
C) neither your weight nor your mass would change.
D) your mass would change, but your weight would not change.
E) None of these is true.
20)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
21) Explain, from a force standpoint, how a rear spoiler on a race car helps keep the car on the
road at high speeds.
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19)
21)
Answer Key
Testname: MAKEUP1
1) D
2) A
3) C
4) D
5) D
6) D
7) A
8) C
9) A
10) A
11) B
12) C
13) B
14) The force exerted on the book by the table is a reaction force resulting from the weight of the book acting on the table.
The net force acting on the book is zero, so the book does not move.
15) C
16) C
17) C
18) A
19) B
20) B
21) Air flowing over the top of the car exerts a force on the spoiler; a component of this force is vertically downward. This
additional downward force helps keep the car on the road.
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