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l. A car roundsa horizontalcurveof constantradiusat a constantspeed.Which
the directionof both the car'svelocity,v, and acceleration,
diagrambestrepresents
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2. The diagrambelow showsa 5.0 kg bucketof water beingswungin a horizontalcircle
of O.7Om radiusat a constantspeedof 2.0 m/s.
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forceon the bucketof water?
What is the magnitudeof the centripetal
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3. How many rotationsper minutedoesa power drill reachafter1.47seconds
at a rateof 1.228rad/s2?
accelerating
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pathof radius12m at a
A 4 . Ok g mo d e la i rp l a n etra ve l sin a horizontal
circular
constantspeedof 6.0 m/s.
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lf the speedof the airplaneis doubledand the radiusof the path remainsunchanged,
forceactingon the airplanewill be
the magnitudeof the centripetal
a . h al fa smu ch
b . t wi cea smu ch
c. one-fourthas much
G, four timesas much
tube lyingflat on a horizontaltabletop.
5 O A ball rollsthrougha hollow semicircular
path
ball afteremergingfrom the tube?
the
of
the
Which diagrambestshows
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and
rotatesin a clockwisedirectionaroundits axis,it undergoes
As a merry-go-round
the
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velocity
of
of 9.80 rad in 2.0 seconds.What the angular
angulardisplacement
merry-go-round?
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O. A 1200kg cartravelingat a constantspeedof 9.0 m/s turnsat an intersection.
car followsa horizontalcircularpathwith a radiusof 25 m to point P.
1r'-iii-kg 1v:$'tt nirs
\t --9m/ 5
forceactingon the car asit travels
a. What is the magnitudeof the centripetal
a r o und the circularpath?
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b. At point P, the car hitsan areaof iceand losesall frictionalforceon its tires.
Which path doesthe carfollow on the ice?
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An athleteruns.at a constantspeed,arounda circleof radius5.0 m in 12 s. What are
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the athlete'sspeedand acceleration?
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A rollercoastercar is movingpastthe top of a loop of diameter14 m asshown
below. The normalforce(directeddownwards)providedby the trackat the top of
the loop is equalto one-halfthe weightof the car.
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What is the speedof the coastercar at thispoint?
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with a time of 3.78 s per rotationat a
\O C. A 35.0 kg boy sitson a merry-go-round
distance
of 175cm from the centerofrotation. Findthe boy'stangentialspeed,and
forcehe experiences.
and centripetal
the centripetalacceleration
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tr-?
\\ O. The diagramshowsan objectof mass3.0 kg travelingin a circularpath of radius1.2
force
by a pieceof stringof length1.9m. What is the centripetal
m while suspended
o n t h e ma ss? f: \" ? rn p 6:?Kg
f F^=1^
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f,q=Tdrne
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is movingdown a rampwith a 7.0 m radiusof curvature.
A 6l.kg skateboarder
the bottom of this ramp he reachesa speedof 7.8 m/s.
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fr\= Gtfg
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at the bottom of the ramp?
What upward force actson the skateboarder
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G\ror(r.1ry)t + GtKS(1,81'/s\ - Fr.
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