HOUSTON COMMUNITY COLLEGE SOUTHWEST
PHYSICS 1401- COLLEGE PHYSICS I
FALL 2003
COMPREHENSIVE FINAL EXAMINATION
Instructor: David Cantu
Monday, December 8, 2003
NAME :
__________________________________
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INSTRUCTION: This booklet carries 25 multiple choice questions . Each has one best
answer from four choices given. Please write the letter (upper case) of your
choice corresponding to the right answer on the space provided. In case if
you do not find answer from the choices given print E on the space provided.
If the question is quantitative, give a brief outline of your calculation that
leads to the number of your choice to get partial credit. The right choice
with a wrong method and or without an outline of the solution won’t earn
you full point.
!! Please use pen(s) (not pencils) to write your answers.
-----1. On planet Z, the standard unit of length is the foose. Ann the Astronaut is 5.90 feet tall on
earth. She lands on planet Z and is measured to be 94 foosi tall. Her partner Rachael is 88
foosi tall. How tall is Rachael on Earth?
A. 5.2 feet
B. 5.5 feet
C. 5.8 feet
D. 6.3 feet
-----2. A right triangle has sides 5.0 m, 12 m, and 13 m. The smallest angle of this triangle is
nearest
A. 21o
B. 23o
C. 43o
D. Not attainable since this is not a right triangle
-----3. On your weeding day you leave for the church 30.0 minutes before the ceremony is to
begin, which should be plenty of time since the church is only 10.0 miles away. On the
way however, you have to make an unanticipated stop for construction work on the road.
As a result, your average speed for the first 15 minutes is only 5.0 mi/h. What average
speed do you need for the rest of the trip to get you to the church on time?
A. 5 mi/h
B. 15 mi/h
C. 35 mi/h
D.40 mi/h
-----4. An automobile driver puts on the brakes and decelerates from 30.0 m/s to zero in 10.0 s.
What distance does the car travel?
A. 150 m
B. 196 m
C. 336 m
D. 392 m
-----5. A taxicab moves five blocks due north, five blocks due east and another two blocks due
north. Assume all blocks are of equal size. What is the magnitude of the taxi’s
displacement, start to finish?
A. 12 blocks
B. 9.8 blocks
C. 9.2 blocks
D. 8.6 blocks
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-----6. A student stands at the edge of a cliff and throws a stone horizontally over the edge with a
speed of 18.0 m/s. The cliff is 50.0 m above a flat, horizontal beach, as shown in Figure Q6.
How long after being released does the stone strike the beach below the cliff?
Figure Q6
A. 3.2 s,
B. 2.8 s
C. 10.2 s
D. 1.83 s
-----7. Assume that the three blocks in Figure Q7 move on a frictionless surface and that a 42-N
force acts as shown on the 3.0-kg block. What is the acceleration, in m/s2, given this
system?
Figure Q7
A. 14
B. 4.3
C. 7.0
D. 6.0
----- 8. Find the acceleration experienced by each of the two objects shown in Figure Q8 if the
coefficient of kinetic friction between the 7.00-kg object and the plane is 0.250.
Figure Q8
A. 0.5 m/s
B. 3.3
C. 1.2
D. 1.9
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-----9. An object moving along the x-axis is acted upon by a force Fx that varies with position as
shown. What work is done in J by this force as the object moves from x = 2 m to x = 8 m?
F(N)
3
2
1
x(m)
2
4
6
8
-1
-2
A. –6
B. +6,
C. +4
D. –2
----- 10. A 1.50 x 103–kg car accelerates uniformly from rest to 10.0 m/s in 3.00 s. Find the
average power delivered by the engine in this time interval.
A. 3.33 W
B. 25000 W
C. 5000 W
D. 3333 W
-----11. A cannon of mass 1 500 kg fires a 10-kg shell with a velocity of 200 m/s at an angle of
45 above the horizontal. Find the recoil velocity of the cannon across the level ground.
A. 1.33 m/s
B. 0.94 m/s
C. 2.41 m/s
D. 1.94 m/s
-----12 Two blocks of masses m1 = 2.00 kg and m2 = 4.00 kg are each released from rest at a
height of 5.00 m on a frictionless track, as shown in Figure Q12, and undergo an elastic
head-on collision. Determine the velocity of each block immediately after the collision,
(v1, v2) in m/s.
Figure Q12
A. (-9.9,9.9)
B. (-16.5,3.3),
C. (-3.3,16.5)
D. (9.9, -9.9)
-----13. A point on the rim of a 0.25-m-radius rotating wheel has a centripetal acceleration of 4.0
5
m/s2. What is the angular speed of the wheel?
A. 1.0 rad/s
B. 2.0 rad/s
C. 3.2 rad/s
D. 4.0 rad/s
-----14. A dentist’s drill starts from rest. After 3.20 s of constant angular acceleration, it turns at a
rate of 2.51 x 104 rev/min. Find the drill’s angular acceleration.
A. 4.7x105 rev/min2
C. both A and B
B. 4.9x104 rad/s2 ,
D. Cannot determine.
-----15. In exercise physiology studies it is sometimes important to determine the location of a
person’s center of gravity. This can be done with the arrangement shown in Figure Q15. A
light plank rests on two scales, which read Fg1 = 380 N and Fg2 = 320 N. The scales are
separated by a distance of 2.00 m. How far from the woman’s feet is her center of gravity?
Figure Q15
A. 0.91 m
B. 1.09 m
C. 1.50 m
D. 1.00 m
-----16. An ice skater spins at 2.5 rev/s when his arms are extended. He draws his arms in and
spins at 6.0 rev/s. By what factor does his moment of inertia change in the process?
A. 2.4
B. 1.0
C. 0.42
D. 0.12
-----17. Which state of matter is associated with the very lowest of temperatures?
A. liquid
B. plasma
C. gas
D. solid
-----18. 44. An ideal fluid, of density 0.90  103 kg/m3, flows at 6.0 m/s through a level pipe with
radius of 0.50 cm. The pressure in the fluid is 1.3  105 N/m2. This pipe connects to a
second level pipe, with radius of 1.5 cm. Find the speed of flow in the second pipe.
A. 54 m/s
B.18 m/s
C. 0.67 m/s
D. 0.33 m/s
-----19. An automobile gas tank is filled to its capacity of 15.00 gallons with the gasoline at an
initial temperature of 10C. The automobile is parked in the sun causing the gasoline’s
temperature to rise to 60C. If the coefficient of volume expansion for gasoline is 9.6 
104/C, what volume runs out the overflow tube?
A. 1.74 gallons
B. 1.18 gallons
C. 0.72 gallons
D. 0.30 gallons
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-----20. One way to heat a gas is to compress it. A gas at 1.00 atm at 25.0C is compressed
to one tenth of its original volume, and it reaches 40.0 atm pressure. What is its new
temperature?
A. 1 500 K
B. 1 500C
C. 1 192C
D. 919C
-----21. A hot (70C) lump of metal has a mass of 250 g and a specific heat of 0.25 cal/gC.
John drops the metal into a 500-g calorimeter containing 75 g of water at 20C. The
calorimeter is constructed of a material that has a specific heat of 0.10 cal/ gC. When
equilibrium is reached, what will be the final temperature? cwater = 1.00 cal/gC. (Hint:
Heat lost by lump of metal = Heat gained by (Calorimeter + water))
A. 114C
B. 72C
C. 64C
D. 37C
----- 22. How much energy is required to change a 50-g ice cube from ice at –10°C to steam at
120°C? cice = 0.5 cal /g.oC, Lf = 80 cal/g , Lv =540 cal/g, cw = 1cal/goC, cs = 0.5cal/goC.
(Hint: Recall the energy temperature curve for water. You have five sections to treat
independently, i.e., warming the ice, melting the ice, warming the water, boiling the water,
and warming the steam)
A. 250 cal
B. 36.75kcal
C. 27.00k cal
D. 2.7 x106 cal
-----23. A system is acted on by its surroundings in such a way that it receives 50 J of heat while
simultaneously doing 20 J of work. What is its net change in internal energy?
A. 70 J
B. 30 J
C. zero
D. 30 J
-----24. In an isothermal process for an ideal gas system (where the internal energy doesn’t
change), which of the following choices best corresponds to the value of the work done on
the system?
A. its heat intake
C. the negative of its heat intake
B. twice its heat intake
D. twice the negative of its heat intake
----- 25. A heat engine exhausts 3 000 J of heat while performing 1 500 J of useful work. What is the
efficiency of the engine?
A. 15%
B. 33%
C. 50%
D. 60%