95.02: An object shown ino+xbis.:8.d gd-oe a ox1)hpr the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force g.d-1obxdi )s8.he o :+pxaroacting on the object at the instant shown?

  05.31: A child is belted into6lyurdm6x d 2d0lo5sd,cn xw jw230 8g a Ferris Wheel seat that rotates counterclockwise at constant speed at an amusement park. x 2 wmndl268 0u3xcw0 gd rd,y5dsl6ojAt the location shown, which direction best represents the total force exerted on the child by the seat and belt?

  08.14: A particle continuously minm56yficmujj **inc; f6c/c )-9 2 cajepfa 0oves in a circular path at constant speed in a counter- clockwise 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 Pjfmn5ipc9mc cjj* -)/ei0*aa6 nf 6 c2;y ucfi.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a cs)fk6eh8rit6 7nz n; lircular path at constant speed in a counter- clnfst7n6hz 8;kel) i 6rockwise 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 clockwis cc,m:mi m.4mhe with constant speed around the vertical circle shown. Which arrow best indicates the direction of the object’s , .4mic:m cmhminstantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end of a string counterclockyxr)en f8qaf xk54+o1 wise in a horizontal cif8q f54)xayn xk+e1rorcle above her head. The figure shows an outline of the mass’s path viewed from above 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 speed around a horseshoe-shazy n4k3n7/+g/ puhw gzped 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 car in zg pwunh4+n/ 73yz/k gtraveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment withkw6 y.q:48*i1gpmrolhi 6jr d a simple pendulum that is released from the horizontal position at rest. 6y8:i1l4 p rjm6dr* qh.woi kgAt 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) point-like object rests 2.0m from sk)llk6.e f(, ik p:dyaaj; k3the 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 coeffikfps i ;kll :(.y)kked6 a,a3jcient 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 circr 1nmu, w*- ;tnctf5(vd7w 8u, djaexwle of radius 0e8xwtwddw57u 1 t -, u;n,vmajc (*nfr.5 m on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration ofaub :f9kc vra a,r)j(8 an object (mass = 50 g) on the end of an 80-cm string rotating at a constaaa)facr, bkv :j r(9u8nt rate of 4 times a second?

  09.24: A point mass moves along a-iwnupo0k2j v6v7p * a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on the mass as it n2p0uva-iv7oj* wp 6kmoves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirled * wt2+snq r+wjhdv0b2z.pv-xzw3f(vu.: lk y in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the bajqv+ .(l*hs 2:.zw0zd+ky -pfbn wxv2 wvru t3ll during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in a uniform circn),rq ;m vy6gtulmc * +u7,xrhular motion. Which of the following statemeg xuvrr+ly mm,6)n,qu;t h7*cnts is NOT true?

  00.19: An astronaut in an orj 3;k+-ni fi58v3oagajd5tdyen8,wm h i(ra: biting space craft attaches a mass m 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 mo3mr8;kwhy d: vi ( 53+-5eg8nj,ajnoiat diaftion would be

  07.22: A mass m is pulled outward un+h5, * gdizkdwa7a/j gtil the string of length L to which it is attached makes a 90- degree angle with the vertical. The mass is releasegd/wk5*gz +ia, j dha7d 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 travellh7r xba )g)0iing on a road in hilly terrain, see figure to the right. Assume the car has speed v and the tops and bottg)ib l0r)a7hx oms 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 spl, 9r9k3 ll;iaoh,- w(rbwdvy eed of 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 figukwol; lr9,hli rd b 3y,vw9a-(re. Which one of the following choices best represents the magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a vertical circle at constant speed. The n6 k8cggfbaw)8.nuu ( * dm5jkmagnitude of annb g856 fcd.u()gmw* kuj k8the net force on the sphere

  11.47: A simple pendulki) .1d n;q c-n/2fft+neeti vum 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 magnitude 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 bof2 )envk ;nnq-idfitce1 +/.t ttom of the arc (point P)?

  16.32: A mass connected to a str egzx3- ,l8np mykg13ving forms a simple 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 fo p3n,1k3xy- gz8mglve rce on the mass (W), and the net force acting on the mass (F) when the mass swings through its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a qg y1sl,04ldk rubber stopper moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smalq1 l,lsd0g4kyler, what happens to the speed v, and the frequency f, of the stopper?

  05.28: A mass, M, is b*8zn)nh bm /uh n u7prox4yxq96lu 5,at rest on a frictionless surface, 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 force applied nu)z5oyhumbl*h 8nqux 4rpb n97,/6x by the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a constant speed of 3.24 m/s in abd ( lkahw43k9 vertically-oriented circle kl3wk9 d hba(4of 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 (labeled Xyma0x 491l+0c rr mwaz andY) are at reston a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and thra ra zmlc0+xyw 041r9mough its center. The distance of the coins from the center 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 of st v-u-,ou h( +pxjf,izdring and moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The string has a length of 2.5vfji +,h(uxo-dpu z-,0 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+qkd(. j zxds 8:yv7tj circular motion as shown in the figure. The string to which the mass is attached has a length of L = 3.00 m and formjyj sdqz.d tkv+:8x(7s an angle of $θ=50^{\circ}$with the vertical. What is the speed of the mass?

  13.23: A small object of mass 11.0g is at rest 30.0 cm from a horizontal rw5pg(f+t1) j+gwzl e disk’s center. The disk starts to rotate from rest about its centeref)wj 5l(z++rgpw g1t 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 w5 3ys1z8jt upkg is attached a distance R =1.75 m from the fixed center of a disk as 8 3tupw5szjy 1shown in the figure. The disk starts rotating from rest with constant 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 circle, starting at tilv;8os-.5ldfcm:8rsq y o i+ he top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an anoomr5fs.c ;vyi d:ls-iq8l 8+ gle 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 a circle, starting at the top, with initial spee.l5rt hx5 oom,zz(h /td 17.0 m/s. The object’s speed increases uni,zh 5xm.olo (t th5z/rformly until 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 1v9lrpzb o r/1rests at the bottom of a bucket. The bucket is spun 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 1 vlob/1rpr9z the block to remain in place in the bucket. When the bucket is 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.