### Potential energy and spring force

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ahn (ka6577) potential energy and spring force ahn - (15011)
This print-out should have 14 questions.
Multiple-choice questions may continue on
the next column or page - find all choiccs
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It takes
2.76J of work
to stretcha Hooke's-law
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The force required to stretch a Hooke's-law
spring variesfrom 0 N to 51.6N as we stretch
the spring by moving one end 5.88 cm from
its unstressedposition.
Find the force constant of the spring. Answerin units of N/m.
l
â‚¬=-Ll|
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a,
003 (part 2 of 2) 10.0points
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Find
the
work done in stretchingthe spring.
r r -.){nl
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D
004 (part 1 of 6) 10.0points
A projectile of mass 0.425 kg is shot from
a cannon, at height 6.6 m, as shown in the
figure, with an initial yetroertyu; having a
horizontal component QA ^l:)=-+
L,T,x
The projectile risesto driidximum heightof
AE abovethe end of the cannon'sbarrel and
strikes the ground a horizorrtaldistarrceAr
past the end ofthe cannon'sbarrel.
/,
005 (part 2 ot 6) 10.0 points
Determine the maximum height AE the projectile achieves after leaving the end of the
cannon's barrel. Answer in units of m.
006 (part 3 of 6) 10.0points
Find the work done by the gravitational force
on the projectile during the motion in its
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trajectory. Answer in units of J. Wn,o,-\$i
(J
')
Ul
OOZ(part 4 of 6) 10.0points
Find the magnitude of the velocity vector
when the projectile hits the ground. Answer
in units of m/s.
008 (part 5 of 6) 10.0points
Find the magnitudeof the angle (with repect F
to horizontal) the projectile makeswhen im9! _r,"^
pacting the ground. Answer in units of ".
,+,
,
009 (part 6 of 6) 10.0points
Find the range Ar of the projectile. Answer
in units of m. ! = )"'- L17t - !,7r' I'ina t ui'vn l'" o
/
Starting from rest at a height equal to the
radius of the circular track, a block of mass
25 kg slides down a quarter circular track
under the influence of gravity with friction
present (of coefficientp). The radius of the
track is 35 m.
The accelerationof gravity is 9.8 m/s2 .
25kg
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t,
Determine the vertical component of the
initial velocity at the end of the cannon'sbarrel, where the projectile beginsits trajectory.
The accelerationof gravity is 9.8 m/s2 .
'4*
If the kinetic energy of the block at the
bottom of the track is 4500 J. what is the
work done againstdiicilof,? Answer in units
orJ. !rJ,.,.
= (k"r=K;)+(Uw-ti,,,-)
011 10.0points
A spring with a forceconstantof 5.2 N/m has
a relaxed length of 2.62 m. When a mass is
ahn (ka6577) - potential energy and spring force - ahn - (15011)
attached to the end of the spring and allowed
to come to rest, the vertical length of the
spring is 3.73m.
Calculate the elastic potential energy
stored in the spring. Answer in units of J.
0L2 (part 1 of 3) 10.0points
A 40.0 kg child is in a swing that is attached
to ropes2.20m long.
The accelerationof gravity is 9.81^ls2 .
Find the gravitational potential energy associated with the child relative to the child's
lowest position under the following conditions:
a) when the ropes are horizontal. Answer
in units of J.
013 (part 2 of 3) 10.0points
b) when the ropes make a 33.0o angle with
the vertical. Answer in units of J.
014 (part 3 of 3) 10.0points
c) at the bottom of the circular arc. Answer
in units of J.
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