ReviewTest
Mechonics
June2008
This yeor there were47 of 85
pailA
Answer all quesfronr in fh FrL
write on the separateanswersheetthe numberof
-Drec-tions(1-35):For eachstatementor que_stion,
-the
word or expression
that, of thosegiven,bestcoirpletesthe statementoi ans\rersthe quesuo;.
I Which is a vector quantity?
(1) speed
(3) mass
(2) work
(4) &splacement
2 A race "car starting from rest accelerates
uniformly at a rate of +.gOmetersper second2.
What is the car's speed after it has traveled
200.meters?
(f) f960 m/s
(3) 44.3m/s
(2) 62.6m/s
(4) 31.3m/s
A ball is thrown straightdownwardwith a speed
of^0,50 meter per iecond from a heiglit of
4.0 meters. What is the speed of thi bdl
0.70 second after it is released? [Neglect
friction.l
(r) 0.50m/s
(3) 9.8m/s
(2) 7.am/s
(4) 15m/s
A^s99cer
playerkicksa ball with aninitial velocity
of 10. meters per secondat an angle of 30.6
above the horGontal. The magnitfde of ,the
horizontalcomponentof the balliiniUal velocity
is
(1) 5.0m/s
(3) 9.8m/s
(2) 8.7m/s
(4) 10.m/s
7 Tro spheres,A and B, are simultaneously
projectedhorizontdly from the top of a towei.
SphereA has a horizontalspeedof aO.meters
per secondand qphereB hasa horizontalspeed
of 20. metersperiecond. Which statement^best
describesthe time required for the qpheresto
reach the ground and the horizontai distance
they,travel? [Neglectfriction and assume&e
grouhdis level.l
(f) Both sphereshit the ground at the same
time and at the samedistancefrom the base
of the tower.
(2) Both qphereshit the ground at the same
time, but sphere A lands twice as far as
sphereB from tire baseof the tower.
(3) Both sphereshit the ground at the same
time, but sphere B lands twice as far as
sphereA fr;m the baseof the tower.
(a) Spt_rerg
A hits.the groundbeforesphereB,
and sphere
-the A landstqiiceasfar asiphere B
from
baseof the tower.
8 In the diagrambelow,a 20.-newtonforce due
north and a 20.-newtonforce due east act
c_oncurrentlyon an ob;'ect, as shown in the
diagrambelow.
North
5 Which oblecthasthe greatestinertia?
(f) a 5.00-kgmassmovingat 10.0m/s
(2) a f0.0-k[ massmovini at I.00 m/s
(3) a f5.0-kgmasimovin[ at 10.0m/s
(a) a 20.0-k! massmovin[ at 1.00m/s
6
{g0.-}dlogam pfrystcs_studentwould weigh
1560newtonson the surfaceof planetX. What
is the magnitude of the accel-erationdue to
gravityon the surfaceof planetX?
(1) 0.038m/sz
(3) 9.8m/sz
(2) 6.1m/sz
(4) 26 m/sz
The additional force necessary to bring the
object into a state of equilibrium is
(t) 20. N, northeast
(2) 20.N, southwest
(3) 28 N, northeast
(4) 28 N, southwest
I A car's performance is tested on various
horizontal road surfaces. The brakes are
applied, causing the rubber tires of the car to
slide along the road without rolling. The tires
encounter the greatest force of friction to stop
the car on
(3) wet concrete
(1) dry concrete
(2) dry asphdt
(4) wet asphdt
10 A car rounds a horizontal curve of constant
radius at a constantspeed. Which diagram best
represents the directions of both the car's
velocity, r.r,and acceleration,a?
}
( 1 )
(3)
)r
t / \
(2)
(4)
I I A 6.0-hlogram block, sliding to the east acrossa
horizontal, frictionless surface with
a
momentum of 30. hlogam.meters per second,
strikes an obstacle. The obstacle exerts an
impulse of 10. newtonosecondsto the west on
the block. The speed of the block after the
collision is
(1) 1.7m/s
(2) 3.3m/s
(3) 5.0 m/s
(4) 20. m/s
12 If a 65-kilogram astronaut exerts a force with a
magnitude of 50. newtonson a satellite that she
is repairing, the magnitude of the force that the
satellite exertson her is
(1)0N
(2) 50. N lessthan her weight
(3) 50. N more than her weight
(4) 50. N'
13 A 1.O-hlogram laboratory cart moving with a
velocity of 0.50 meter per second due easl
coilides with and sticla to a similar cart initialll
at rest. After the collision, the two carts move ofl
together with a velocity of 0.25 meter per second
due east. The total momentum of this
frictionless systemis
(1) zero before the collision
(2) zero after the collision
(3) the samebefore and after the collision
(4) greater before the collision than after the
collision
14 StudentA iifts a 50.-newtonbox from the floor tc
a height of 0.40meter in 2.0 seconds.StudentE
lifts a 40.-newtonbox from the floor to a heighl
of 0.50 meter in 1.0 second. Compared tc
student A, student B does
(1) the samework but developsmore power
(2) the samework but developslesspower
(3) more work but developslesspower
(4) lesswork but developsmore power
15 While riding a chairlift, a 55-hlogram sher ir
raiseda vertical distanceof 370 meters. What ir
the total change in the sher's gravitationa
potential enerry?
(1)s.4x 1orJ
( 2 )5 . 4 xr d J
(3)2.0x loa]
e ) 2 . Ax r d J
16 The work done on a slingshotis 40.0joulestt
pull backa 0.I0-hlogramstone. If the slingsbo
projectsthe stonestraightup in the air,what i
the maximumheightto whichthe stonewill rise'
[Neglectfricdon.]
(l) 0.4rm
(2) 4Lm
(3) 4r0m
(4) 4.1m
17 A 0.686-meter-longwire has a cross-sectiona
area of 8.23 x IF metef and a resistanceo
0.125 ohm at 20o Celsius. This wire could b,
made of
(1) aluminum
(.r/ nichrome
(4) tungsten
(2) copper
JO A JourerSequvalent to a
(1) N.m
(2) N.s
+1
(3) N/m
(4) N/s
37 The weight of a chicken egg is most.nearlyequal
to
(3) 100N
( l ) lO-3 N
(4) 102N
( 2 ) IO-2 N
38 Two forces act concurrently on an object. Their
resultant force has the largest magnitude when
the anglebetween the forces is
( 1 ) 00
(2) 30"
(3) 900
(4) 180"
A bicvcle and its rider have a combined massof
80. hlograms and a speed of 6.0 meters per
second. What is the magnitude of the average,
force neededto bring the bicycle and its rider to
a stop in 4.0 seconds?
(1) r.2 x 102N
(2) 3.2x ld N
(3) 4.8x 102N
(4) 1.9x 103N
40 Gravitational forces differ from electrostatic
forces in that gravitational forces are
(l) attractive,only
(2) repulsive,only
(3) neither attractive nor repulsive
(a) both attractive and repulsive
50 A"spring
in a toy caris compressed
a distance,
r.
wnen released,th.espringreturnsto its original
kngtt, transferring iar" energy to the car.
Consequendy,
the carhaving*i, - moveswith
speed 1).
constant,k, of the car'sspring
,?"1:ft"
rn terms oI:pring
m, r, and o. [Assumean laej
mechanicalsystemwith no loss of ;;"rSrJ
[Show{l work, includingtt " "qu"Uonsusedto
derivethe springconstan"t.]Jz1'
vvrucn graPn oesr rePreserrfs[rre rerauuusr-uP
between the elastic potential energFstored in a
spring and its elongation from equilibrium?
cn
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Elongation
c
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( 1)
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Elongation
tr
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Elongation
Elongation
(2)
(4)
42 A car with mass m possessesmomenfum of
magnitude p. Which e4pressioncorrectly represents the hnetic enerry, KE, of the car in
terms of m arrdp?
(l) tiGG=!p
2m
(3)o=i*
Baseyour answersto questions5l and 52 on the'
information below.
A 7S-hlogram athlete jogs 1.8 hlometers
aionga straightroad in 1.2 x 103seconds.
5l Determine the averagespeed of the athlete in
metersper second. 1t1
52 Calculate the average kinetic energy of the
athlete. [Show all work, including the equation
and substitutionwith units.] tzl
A car,initially traveling at 30. meters per second,
slows uniformly as it shds to a stop after the
brakes are applied. On the a:<esin yar ansuer
bookla, skerch a graph showing the relationship
between the kinetic enerry of the car as it is
being brought to a stop and the work done by
friction in stopping the car' tll
pase your answers to quesUons ,)d and b9 on the
information and &agram below
60 A 1500-hlogramcar acceleratesat 5.0 meters
A soccerball is hcked from point P, at an
angle above a horizontal field. The ball
follows an ideal path before landing on the
fteld at point Pr.
per secondz on a level, dry, asphalt road.
Determine the magnitude of the ne^thorizontal
force acting on the-car. ttl
61 Calculate the magnitude of the centripetal
-Sun,
Pi
Pf
Horizontalfield
force acting on E-arth as it orbits the
a circular orbit and an orbital speedof
T:l*ilg
S O9 I 104meters per second. lShow ai] work,
including the equltion and substitution with
units.l t2l
58 On the diagram in your ansu)erbooklet,draw an
arrow to represent the direction of the net force
on tlle baliwhen it is at position X. Label the
arrow 4r. [Neglectfriction.] trt
59 On the diagramin your ansrDerbookla,draw an
arrow to represent the direction of the
accelerationof the ball at position Y. Label the
arrow a. [Neglectfriction.] ttl
Baseyour answersto questions63 through 66 on the information and data table below.
A l.O0-hlogram masswas dropped from rest from a height of 25.0 meters above
Earth s surface. The speedof the masswas determined at S.0-meterintervals and recorded
in the data table below.
DataTable
HeightAboveEarth'sSurface
(m)
25.0
20.0
15.0
10.0
5.0
0
Speed
(m/s)
0.0
9,9
14.0
17.1
19.8
22.1
Directi,ons(63-66): Using the information in the data table, construct a graph on the gndin Ua)r anfl)er
booklet,following the &rections below.
63 Mark an appropriatescaleon the a:rislabeled"Height Above Earth'sSurface(m)." ttl
64 Plot the data points for speedversusheight above Earth's surface. ttl
OD
Draw the line or curve of best ftt. t1l
66 Using your graph, determine the speed of the mass after it has fallen a vertical
&stanceof L2.5meters. f tl
Baseyour answersto questions71 and 72 onthe information below
A 747 jet, traveling at a velocity of 70. meters per secondnorth, touches down on a
runway. The jet slowsto rest at the rate of 2.0 meiets per second2.
71 Calculate the total distance the jet travels on the runway as it is brought to rest.
[Show aii work, including the equation and substitutionwith units.] lzl
72 On the diagramin your ansu)erbooklet, point P representsthe position of the jet on
the runway.^Beginning at point P, draw a vectoito .ep.esenf the magnitudl and
direction of the acceleratibn of the jet as it comes to rest. UsJ a scale of
L0 centimeter = 0.50 meter/second2. tzl
Baseyour answersto questions73 and 74 on the information below.
Io (pronounced'EYE oh") is one of Jupiter'smoonsdiscoveredby Galileo. Io is slightly
,
larger than Earth's Moon.
The massof Io is 8.93 x 1022hlograms aiid the massof Jupiter is 1.90 xLO27hlograms.
The distancebetween the centers oflo and Jupiter is 4.22 i rb8 meters.
73 Calculatethe magnitude of the gravitational force of attraction that Jupiter exerts
on Io. lShow all work, including the equation and substitutionwith units.] t2l
74 Calculate the magnitude of the acceleration of Io due to the gravitational force
exerted by Jupiter. [Show all work, including the equation andsubstitution with
units.l t2l
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