95.02: An object shown in the accompanying figurec /po(bl4 5ob.-ll lvp moves in uniform circular motion. Which arrow best depicts the net force acting on the object atpv o 54(lbocl. /bllp- the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rot4 anq2o mhxu+4ates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total fa4u h2 mo+4nxqorce exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular s05gz.,hqjpv6 s(vxk 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 tqg zkvh5.x(6,ss pv0jhe circle from Point P.
What is the direction of the average velocity during this time interval?

  08.15: A particle continuously moves in a circula-bkp) :8xg0pntuks .gk p,,vcr path at constant speed in a counter- clockwise dit0g)v ppksg cb k.xpu:8,n-k, rection. 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 constant speed around tuz-x g3o;ie;+ 0v zxquhe vertical circle shown. Which arrow best vx x+0g;;qiu3ezzu-oindicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connecteau(rg6excvsh2u u/ 4x d 37lf5e5lx;ed to the end of a string counterclockwise in a horizontal uvx7rs 42exau5h(d3 u5ef e;lg c/x l6circle 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-shapee wacqm3)6p j2,loez;d path as shown with the arrows in the figure. Which one of the following choices best describes the direction of theow)z6,m;cj ple ea23q average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experiment with a simple pendzdw1s0h g )2jy)qfii (ulum that is released from the hoz1)g hs)2idiqw0 (jy frizontal 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) point-like object rests 2.0m from the center of a rough bu)87q eouz3q qttf** qvnq6qx+7))ip oj;fq turntable as the turntable rotates. The period of the+ *i)qvfpo 3 *qqxetzjqqb ;6t q 7n)7o8fuq)u turntable's rotation is 5.0 seconds. The coefficient of kinetic friction between the object and turntable is 0.50, while the coefficient 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 rxwo5v75 ,t i d4:;c-oismijm moving in a circle of radius 0.5 m on a horizontal frictionlesri5c7v54s,:xj i wm- mdi;o ots surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (maeael yb,5l.cm 43w6 eoqen n62ss = 50 g) on the end of an 80-cm string rotaey53 . lwel2mc4 q6ebaneo 6,nting at a constant rate of 4 times a second?

  09.24: A point mass movasvzf/js k k7(x. /x,qes along a horizontal circular path of radius 0.8m with a constant kinetic energxj f ks.v7zsa/x, qk/(y 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 strin vusg0r2fi pmj.6:a8e z *g8tcg and whirled in a horizontal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the ball during each revoluties.r2vifg zg* t8 j uc6p:a8m0on is:

  99.22: A child whirls a ball at the end of a rope, in a uniform cirgl ;e41v4myrdx0uo,k cular motion. Which of the following statemxmv ;rudle0 4g,oy14kents is NOT true?

  00.19: An astronaut in an orbiting spacx h : y:a6vni+ncxx/s)e 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 maxxv6casx n/ nh y:i)+:ss, radius, and speed were all to double the tension required to maintain uniform circular motion would be

  07.22: A mass m is pulled outward until the string of length Lr-gj xcc1dj1+kg +1 zc to which it is attached makes a 90- degree angle with the vertical. The mass is released from rest and swings through a circular arc. What is the tension in the string when the mass swings throug1+rc- x1kc1zcd+gg jjh the bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrainf)e;gt75u7vueqrsr) vsl)rh 0 9o +wx, see figure to the right. Assume the car has sp v; +)lhvgt)eqr wuf077 s)59sroru xeeed v and the 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 movi g ;4 bvyjsu6b2 0w;vrk;q9fmes over a hill at a constant speed 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 figure. qmrku;9g 6w24ijfvs;; v b0yb 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 coeg6va6/l do4* miac ss 7xyp .)sxo /kd:;pxd-nstant speed. The magnitude of the net force oc.dea/xpsdd7pk6/- 4)sxi:xao my l; v*s o6gn the sphere

  11.47: A simple pendulum of length Lhasa point mass M released fromwmkut1ap4 hr 8e4 *h8h 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 describesh8thu4ahkwm*e p84r1 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 simple : w9.kjs du09bhuzl1 jpendulum. 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 netz.0:j u lwbdj9u9h 1sk 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 rubber stopper;,xj; c8o1zgjvhiv4 os :ez vt *po:2z moving at a constant speed in a horizontal circle. If tho,ic 41op8sv:z *x ;t vgvzo;:zjj2 ehe 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 surface, connected t:)q zlrnqefn(dn4+b,o 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 nfn zr+(:),e 4 ldbqnnqecessary force 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 3.24 m/s .8nkd/is h1y8k6zd vh in a vertically-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 d nih88ysk/.6 vdkz1h circle?

  14.23:Two small identical coins (labeled X andY) are at reston a horizon(ruk fqd4f04m xxls+ jgcpyo7xm)-7yl h 8 5g8tal 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 center of disk is relatedfrk 847l(hmyqjxxs5gx8 f7mogcd u p y+4-0) l 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 string an xpa-l49ll:z wd moves about the string’s fixed end in alz -l9apxw4 :l conical 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 uni5c mb0c,mt0pc form circular motion as shown in the figure. The string to which the mass is attached hp c,50bmtm0ccas 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 masss y 8kn)a:9hau 11.0g is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant angular aynhaa u)k :s89cceleration 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 -cgp 4t1tf+6hzz, hp1sda bp)kg is attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotpahh f1 cd ,-gtp4p+ t1bz)6szating 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 the top, with initia 2 p2uvhls*g8el speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through anl2hvs2 8eg *pu 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 a circle, starting at th*9 mpz:gz,a khjf y(6te top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved9mtz za, yp:kfhj*6 (g 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. ouj.fhf5d 600ra +6kfdl zw(uThe 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 enou6fdwz0 5. j+hua(f0urlkd f6 ogh for 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.