ahn (ka6577)- Circularmotion - ahn - (1b011)
This print-out should have 11 questions.
Multiple-choice questions may continue on
the next column or page - find all clroices
before answering.
001 (part 1 of 2) 10.0points
An amusementpark ride consistsof a rotating
circular platform 8.78 m in diameter from
which 10 kg seats are suspendedat the end
of 3.54 m masslesschains. When the system
rotates,the chainsmakean angleof 40.f with
the vertical.
The accelerationof gravity is g.8 mfs2 .
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What is the speedof eachseat? Answer in
units of m/s.
002 (part 2 ot 2) 10.0points
If a child of mass49.1kg sits in a seat,what is
the tensionin the chain (for the sameangle)?
Answerin units of N.
003 (part L of 2) 10.0points
An amusementpark ride consistsof a large
vertical cylinder that spins about its axis
fast enough that any person inside is held
up against the wall when the floor drops away
(seefigure). The coefficientof static friction
betweenthe personand the wall is p and the
radius of the cylinder is ,R.
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004 (part 2 of 2) 10.0points
Supposea person whose mass is m is being
held up against the wall with a constanr rangential velocity,u greater than the minimum
necessary.
Find the magnitfirdeof the frictional force
betweenthe person\andthe wall.
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ahn (ka6577)- Circular motion - ahn - (15011)
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Find its centrioetal acceleration. Answer
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0O7 (part 2 of 3) 10.0points
continuesto fly along the same horizoninereasesits speed aL the rate of
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the magnitude of acceleration under
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new conditions. Answer in units of
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008 (part 3 of 3) 10.0points
nd the direction of acceleration relative to
he direction of motion under these condiions. Answer between -180' and 180'. Ano.
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swer in units of
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005 10.0points
A ball rolls around a circular wall, as shown
in the figure below. The wall endsat point X.
f-',
009 10.0points
A racing car is traveling on a circular race
courseof radius 574 m at a speedsuchthat it
1.32rev in 1 minute. The massof the
car is 1220kg.
What is the centripetal force acting on the
car? Answerin units of N.
01-0(part 1 of 2) 10.0points
A car rounds a slippery curve. The radius of
curvature of the road is R, the banking angle
with respect to the horizontal is 0 and the
coefficientof friction is p.
When the ball gets to X, which path
the ball follow?
L. Path C
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2. Path A
3. Path D
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4.Path E
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5. Path B
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006 (part 1 of 3) 10.0points
A hawk flies in a horizontal arc of radius
18.6m at a constantspeedof 3.9 m/s.
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What should be the car's
that there is no frictional force
car and the road?
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ahn (ka6577)- Circular motion - ahn - (15011)
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011 (part 2 of 2) 10.0points
What is the minimum speedrequired in order
for the car not to slip?
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p"sin9* cosd
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cosd- p,cos?
3. u*in:
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p,sin?- cosd
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g R(sin? -| p cos9)
p,sin9* cos0
6.'u*in:
7. u*in -
g R(sin? - p,cos0)
gR(sin0 - p,cos0)
p,sin?* cos0
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