95.02: An object shown in the accompanying figuevz62egi0j(o2rv f k3re moves in uniform circular motion. Which arrow best depicte g23e6r0kvz(jvfo2i s the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates countercc0 pgcuo h3ho( 96s, 2)vbqhqh9x, iyplockwise at9ip oc6s y 2vhbgx9hoq03) c q(hhu,p, constant 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 circpd:14l* -do p sm(gsxvular 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. 4p*o m- :ls1sp(dgvdxPoint 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 movesi .2b k7tb9sqq 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 9bqbk7q sit2.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 the veed 3yr pv,c.kf-b8jnt-1q,oe rtical circle shown. Which arrow best indicates the direction of the objecto83cyepjt1dk,- -,v n rqef.b’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the enficvk* rb xmb.3k2 a5316hccud of a string counterclockwise in a horizontal circle 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*3 cma5 1fxi. hr6vkk2ubc3cb 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 horse2nyd.hew 8ces4p 4ki4shoe-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 car in traveling from Wtokw4s yhcn4ed 2pie48. X?

  08.35: Astronauts on the Moon perform an experiment with a simple pendui6itmkda/ f ,0lum that is released from the horizontal position at rest. At the moment shown infd a0m6,ii/ kt 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) n7my;4r9 uq ucpoint-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 0.5;4 u cmuqrny790, 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*go uq)8b3xk j necessary to keep a 1. 0 kg puck moving in a circle of radius 0.5 8*k qxu)j3o gbm on a horizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal yh(,4p sj1f edt7d4uoacceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 timespjed, 7 41 shudtfo4(y a second?

  09.24: A point mass moves along a horizontal circular path of radius 0 +70q mwm o.flq-nk:xz.8m with a constant kinetic energy of 128J. What is the f+xn o7q-z0wmkl.:qmmagnitude 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 and whirled in a horizol((:f fs-aho*ls +;y s6nbu unntal circle at a constant speed of 6.0 m/s. See figure to the right. The work done on the ball during eachnl sh(nb6 l s;syu*f(:u+of-a revolution is:

  99.22: A child whirls a ball at +tj:oku ao(4lbv 2lo 8the end of a rope, in a uniform circular motion. Which of the following statements isbjl2tu4 ol+ao k(ov8 : NOT true?

  00.19: An astronaut in an orbiting spautt ) .9d1espcrj-(bw ce 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 tenwbp c)1s.t9d -ruej (tsion in the string is F. If the mass, 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 lengtfal ujq/rqme-d q9r5:- u*nhp1t /,jrh L to which it is attached makes a 90- degree angle with the vertical. The mass is release1pf /ju q5djnm-ru9,h /q:l*et-arr q d 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 apvt .p4xpq,bvp6a23+ y -edod road in hilly terrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills have radius of curvaturetq+e 6.bay,4-2pp dvvdp x3po R. The driver of the car is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a p;z;5i;b2x xrxi(v tuv9vr5v 7 d1.saf4gikk 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. Which one of the followingsbv9ixgra2t; ki174 ;;f(5r5udvxv.pzkxiv choices best represents the magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere is movg,up (/jdy q7hing in a vertical circle at constant speed. The magnitude /(h jg,pydqu7of the net force on the sphere

  11.47: A simple penduhaftdh x 7z7h u h(:l8j;io02klum 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 swingsu 0 2(lzx7hfojhdh7it;:ak 8h at the bottom of the arc (point P)?

  16.32: A mass connected to a stringa.1y :2d s0vl8oifc bg 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 force on the mass (W), and the net force acting on the mass (F) when the mass swings through its lowest pi: ayd bg01c2sv.lf8ooint?

  04.41: A centripetal force of 5.0 newtons is applied to a rub/s4*pgzlku 9 5 ks+(eoiopmajn()bl7ber stopper moving at a constant speed in a h(nzsb+ kaj95( oplkgm ol )i4/e*p7suorizontal 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 surface, connected to an ulpen.e)b9e*(w i u9 bideal horizontal spring that isu( .lb)ie*w9epb u 9en 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 by the person to hold the mass stationary there?

  12.22: A girl swings a 4 3 :kh1keo.fh:i7f- kv-ji 5oc*yjo yv.0 kg mass with a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acting on the mass when it is at the low hov5*i:o 3 cy-ojjk kvifke-.h:7 yf1est point of the circle?

  14.23:Two small identical coins (labeled X andY) are at resf;p2j r58y/wcfjjfcz +oc- 2s 0r; fjhton a horizontal disk rotating at a constant rate about an axis perpendicular to the plane of the disk and through its center. The fy02j o5f ;sjc-r;p cwffz 8j+hj r2c/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 ofjqi;hoy,)ax6 string and moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The str,q ji)o6h ay;xing 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 shjx )d:bs.gv3r w,w/b2q nm84 y sveva6own in the figure. The string to which the mass is 623j8y/bm):vq4w ve ss.vwgd x r,nbaattached 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 mass 11.0g is at rest 30.0 cm from a horizontal uhg 2p 8h/t56f wffem1disk’s center. The disk starts to rotate from rest about its center with a constant angular accelera6h m u2t8g/ffew5 h1pftion 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 4j 1zri gdjcesbb795-8 js ;lnM = 2.0 kg is attached a distance R =1.75 m from the fixed center of a disk as shown ic5-94e7jn1brdlz ;g jib8 s sjn 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 mov a73p7rir+c9wv5u jp:a lrr .qes in a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it:57+37a.cq pjri wul 9arpvrr 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 final speed of the object?

  16.40: An object moves in a c zfpts/)n2zu/amj 8 vccor.93ircle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has movez/n.9p3c)s rza2/ct fuv8o jm d 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 sftmpt7idc5 ego4 om 5pd6.j(6pun in a vertical circle of radius L by a rope. When the bucket reaches f( 6p5t pt co4dg .6o7mj5imedthe highest point in its motion, it moves just fast enough 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.