95.02: An object shown 1eha:1i dm+3(zw f(e adp m(vsin the accompanying figure moves in uniform circular motion. :fsh11 (iewdzp( m(d3eva ma+ Which arrow best depicts the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferrisxua )id( l2p7x Wheel seat that rotates counterclockwise at cxlixa(d p2u7) onstant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular path wav1fs*/xo q-4ml h 3oat constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this circular pa/f m o-4l1xh3osaw* qvth from point P to point Q. Point Q is exactly half-way around the circle from Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a circular path at constant speed i)1j+m4djv ;oug r0e 1pyfsp,u5f mu 4jn a counter- c,u uyfdjmg) usep;o+1 r01pf4jvm54jlockwise direction. Consider a time interval during which the particle moves along this circular path from point P to point Q. Point Q is exactly half-way around the circle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise with cosckn +4m oajkir:dn7x0.(i 6c4p3bpq nstant speed around the vertical circle shown. Which arrow best indicates the directrj x3.( p n6q74skbci:+ic akm4po0dn ion of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the eqk koi*7ae *f;nd of a string counterclockwise in a horizontal circle above her head. The figure shows an outline of the mass’s path viewed from f*k7 ; aoqe*ikabove the twirling mass. If the girl needs the mass to pass through the point labeled P in the figure, at which lettered point on the path should she let go of the string?

  15.23: A car moves with constant speeypbgx6 eer :6-d around a horseshoe-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the direction of the average acceleration of the-bpy6 6ex:g er car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment,3*wv q10r m8bcr1dxvm 8mrghcqa e94 with a simple pendulum that is released from the hcm 3mrxr *gc0841ra,1vbdqh 89vweq morizontal position at rest. At the moment shown in the diagram with $0^{\circ} < \theta < 90^{\circ}$ , the total acceleration of the mass may be directed in which of the following ways?

  03.19: A heavy (2.0 kg) poi db cpz8qkmzi80x7:(qnt-like object rests 2.0m from the center of a rough turntable as the turntable rotates. The period of the turntable's rotation is 5.0 seconds. The coefficient of kinetic friction between the object and turntable is 0.50, while the coe 8c7d8(q z bziq0kpmx:fficient of static friction is 0.80. What is the magnitude of the force of friction acting on the object?

  07.19: What net force is necessary to keep a 1. 0 kg puck moving in a circle of p;9epc (sz22ivrzqs. radius 0.5 m on a horizontal frictionless surfacezzpqi;c9 sp ev(2 s2r. with a speed of 2.0 m/s?

  05.03: What is the centripetal d 8g,f rb5lan0acceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4rab 8 flgn,0d5 times a second?

  09.24: A point mass moves along a horizontal circular path/ yt+l7o0me:de:dt ub of radius 0.8m with a constan7 :+e/tm ydt0ebulo d:t kinetic energy of 128J. What is the magnitude of the net force acting on the mass as it moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string o0o/hpbv qlb1jx ts2 - s u4vl5g*4x7qand whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure /bxoq x v5stg1o*p4l huv 4lbs- j02q7to the right. The work done on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circulymn hbzut1r(,-q4b/ vfj +lw 1ar motion. hjuf4l (, tq-byz/v wn+mr1b1 Which of the following statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches a mass nrl f- cu508r6k9edtdm to a string and whirls it around in uniform circular motion. The radius of the circle is r, the speed of the mass is v, and the tension in the string is F. If the mass, radius, and speed were all to double the tension required to maintain uniform circular motion wdd5ft609lrkcrn e u8- ould be

  07.22: A mass m is pulled outward until tw* j16yu) karo-newk/j6 ocm7 gr9bg/he string of length L to which it is attached makes a 90- degree angle with the vertical. The mass is relr9 my j6 cw-o/r/kuboegngjak* )w761eased from rest and swings through a circular arc. What is the tension in the string when the mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see f8h f1pwlabqtzh2;m* 7 igure to the right. Assume the car has speed v and the lawzf t1p78hq mb;2h*tops and bottoms of the hills have radius of curvature R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed ofnjcow /4ds9 64m -ywror5y,ne 12.0 m/s. At the very top of the hill, the shape of the road can be approximated as a circle with radius 25 m, as indicated in the figure. Which one of the following choices best reprj9n-cr 6s ,d/wnmewyyoo45r 4 esents the magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a verticxsrc 04fn 58(ruer*xdi1t o 7jal circle at constant speed. The magnitude of nefsi7c51 ur8*4d xr0r xoj(tthe net force on the sphere

  11.47: A simple pendu x+gt.7wbc hp 63sulyot1 ,8nglum of length Lhasa point mass M released from rest from the horizontal position shown. In the absence of air resistance and friction, the mass swings through the arc of a circle. Let T represent the magnitude of the force from the string on the mass (tension), G represent the magnitudx+nt6gs 87tw,1pyuch b.g 3 loe of the gravitational force acting on the mass by the earth, and F represent the magnitude of the net force acting on the mass. Which one of the following choices describes the relationship among these forces when the mass swings at the bottom of the arc (point P)?

  16.32: A mass connected to a string forms a simplp 2n0pta5k r7fe pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the following choices correctly ranks the magnitude of the tension in the string (T), the gravitational force on the mass (W), and the net force acting on the mass (F) when the mass swings through its lowest poap0fkn75 tpr2int?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stop 2;slt/8u9vktjarwbt1ufe .pl ji qu4m g77+ :per moving at a constant speed in a horiz;uttub .mjj 27v8/qu w +lafk9gtip:e1l r74sontal circle. If the same force is applied, but the radius is made smaller, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless yfab +d:s lgf.spmb u:030a5ksurface, connected to an ideal horizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this location by applying a 10 N force. The spring is brought back to equilibrium and the mass connected to it is now doubled to 2M. If the spring is extended back 30 cm from equilibrium, what is the necessary forceg fu 0s3.p :b:kma+lydsbf 5a0 applied by the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a constant speed of 3.2+ncv ceb 6+tz rorhab-69(* id4 m/s in a vertically ntr+ icov6heb6b(z d- *ac+9r-oriented circle of radius 0.75 m. What is the net force acting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (la k6y:3nyj4d uebeled X andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The distance of the coins from the cente 6nydju: 4ek3yr of disk is related by $d_x=\frac{1}{2}d_x$. Which one of the following choices correctly identifies the relationship between $f_x$and $f_y$ , the frictional force on coin X and on coin Y, respectively?

  15.40: A 2.0 kg mass is connected to the end ci,q0 ;r/mdhh pe w3t(of string and moves about the string’s fixed end in a conicahtcpd03 /( r q;iwmeh,l motion with a constant speed of 4.0 m/s. The string has a length of 2.50 m and forms an angle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mass is in uniform circular motion as shown istu0d4(ju/ k dn the figure. The string to which the mass is attachedsudj tu (/d0k4 has a length of L = 3.00 m and forms an angle of $θ=50^{\circ}$with the vertical. What is the speed of the mass?

  13.23: A small object of ma gfu*5 j)3yfk,xiv 3 (iozii4css 11.0g is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate frofkv(g*ic4zf 3 ii3y i o5u),jxm rest about its center with a constant angular acceleration of $4.50 rad/s^{2}$ . What is the magnitude of the net force acting on the object after a time of t=1/3 s if the object remains at rest with respect to the disk?

  10.35 A point object with mass M = 2.0 kg rqe 54(ec ;oumis attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from rest with conse4eu(rmco; q5tant angular acceleration $α =5.00 rad/s^{2}$ about an axis perpendicular to the plane of the page through the disk’s center. After how much time (in seconds) is the tangential component of the point object’s acceleration equal in magnitude to the centripetal component of the point object’s acceleration?

  16.39: An object moves in a ciwlkt/ zmy l7 3,+ 3pv.i0mlcbhrcle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclock3p/ml0lhwk.7z c,vt bi +ml 3ywise through an angle of$55^{\circ}$. The average acceleration for this motion is $9.8 m/s^{2}$directed straight downward.
What is the final speed of the object?

  16.40: An object moves in a9 ooh n z(ld8sd-)q4ycr u:fu- circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly u)-9r(u qnuhfcdz4d :l8o y o-sntil it has moved counterclockwise through an angle of$55^{\circ}$. The average acceleration for this motion is $9.8 m/s^{2}$directed straight downward.
What is the time for this motion?

  17.38: A small 2.0 kg block rests at the bottom of a bucket. The bucket is spun,pupp ju +u ;m5jj(s,4mkt8 wr in a vertical circle of radius L by a rope. When the bucket reaches the highest point in its motion, it moves just fast enough for the block to remain in place in the bucket. When the bucket j uj8 s4p,jm5(t,;puukrmw+pis at an angle $θ=30^{\circ}$from the vertical, as seen in the figure, what is the magnitude of the normal force (perpendicular to the surface) provided by the bucket onto the block? Note that the direction of the gravitational field is indicated in the diagram byand that the block does not touch any sides of the bucket aside from the bottom of it.