95.02: An object shown in the accompanying figure moves in uniwbspug+bblak)4,y-v06g 5ok jm9 qi ( form circular motion. Which arrow best depicts the net force acting on oybsb)-lbwqj4,mk k(09 vpa6 iu+g5 gthe object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates6uy(3 uwh6yw y counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the childyw u6(6huw3y y by the seat and belt?

  08.14: A particle continuously moves in a circular path at constant spznabl h1pwj;rc/7yr;25 d 8 mxeed 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 hal2 zh/crwp5;jlb1a yx;d 8 7rmnf-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 speeh,fr dq0w(ofcx96g- djw(e :3sumai ;d 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 :(u aw6w ghrd mo3e9ifcd0 ;fxj-,s q(around the circle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise x45*jqyf4(+ilnr msa ev+n b8with constant speed around the vertical circle shown. Which arrow best indicates the direction of the object’4j4+nibxn+ erv5 a8y*(fmsql s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirlsnqk diwt0 31h-s;ag-f a small mass connected to the end 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 tds;w0qk3 fhi-a- tn1 ghe 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 speetg:*o)kf7uf/ a qff2 ad around a horseshoe-shaped path as shown with the arrows in the figure. Which one of the following choices best describes the a 7a/kfo fftg:qf2*u)direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon kapdyrgh3 89u2gz, b. perform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in the diagramdbyk9 .z8hgurg,pa 23 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 -m yv/(7fjax o2x3 ssrcenter 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 coefficient of static friction is 0.80. What x3smj(y7o r/ ax fs-v2is 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 circt623 l4 evviewle of radius 0.5 m on a horizontal fricti23e 6tilvwv e4onless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleratie81yso64y- 0mii .nwwg ymh4 fon of an object (mass = 50 g) on the end gmyn- myi .w6 4 h148s0wifoeyof an 80-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moves a// p+/z(ic;fapkg0 zh3dd b rmlong a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net forz/a/0db hpfm; /gc d rzk3+p(ice 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 ho9rc1b3jau :c nrizontal circle at a constant speed of 6.cr1c9jn3a bu: 0 m/s. See figure to 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 circula+, e9eqyif8w5tql0m s r motion. Which o,liwmt e qf 9805syq+ef the following statements is NOT true?

  00.19: An astronaut in an orbiting space crafwfo6b 5 0bq8cst attaches a mass m to a string and whisb0 c5qw 86fobrls 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 would be

  07.22: A mass m is pulled outward unty0xmt*f onddg- p)5:f il the string of length L 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 : f-*mfntd)yop d0g 5xthrough the bottom ofthe arc?

  94.15: A car is traveling on afl4ct5qu- fc9 road in hilly terrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills have l4-tqc5c fuf9 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 of ol3k-r s/7k2xapb -pka+tgcxm2,k e (12.0 m/s. At the very top of the hill, the shape of the road can be approxima+ x2eg7(a p kt3-o k-brx/ck2lpms,akted as a circle with radius 25 m, as indicated in the figure. 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 dh k**9uqq y8tconstant speed. The magnitude 9tud*qhk*8qyof the net force on the sphere

  11.47: A simple pendulum of length Lhasa point ma)x.ubwn,9 a m;idryk +ss 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.w bkxu 9 ,.a+dn)ym;ir 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 bottom of the arc (point P)?

  16.32: A mass connecte9hdk2l2lv q w(d to a string 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 fovk(9 2wllq d2hrce on the mass (W), and the net force acting on the mass (F) when the mass swings through its lowest point?

  04.41: A centripetalbnc;3ho/z + pxus6dj 3 force of 5.0 newtons is applied to a rubber stopper moving at a constant speed in a horizontal circl+up3hj63b noz/d c;x se. 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 wy (,wex e3-asg7:lh gan 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 se g3l,-7h( awx: egwyforce applied by the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass wm-yeb* (iyde4mf(c/ q ith 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 lowest*mycq- b d /eyem((if4 point of the circle?

  14.23:Two small identical coins (labeled X andY) are at reston a horizont3suk. ,uas v:frix0o3 al 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 u ,.v:uaxfsr3kosi30 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 connected0iemtc es1lv8w;5 r .a to the end of string and moves about the string’s fixed end .;cvr8lmae1ws05 i etin a 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 uniform circular motion as shown inc upz1 aq9+8m*fojp4bwavqz.r m ;). i the figure. The string to which the mass is attached has a length of L = 3.00 m and forms an aj.p9 a +qqwi bm1)48a fzrzmu*.ov cp;ngle 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 hori;qdshaf-2 wf 2zontal disk’s center. The dd; h fq22swf-aisk starts to rotate from 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 is attached a distance R =1.75 m fron cntcn3bf.p(/ k d)s3z/f2m lm the fixed center of a disk as shown in the figure. flmd / 3tnf.)z3n pnsc2kbc(/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 circl4+ld 7yojnf7 4e,gkgzx o/va,n. xs6me, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly unt x4yk mjz,,eanslv7g7/x . 6 og+d4ofnil 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 final speed of the object?

  16.40: An object moves in a circle, starting at the jm82vg48l j1r lxp1ietop, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counter2e 1 8vr8 m4p1jilljgxclockwise 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 resg2eops3:1c k cts 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 poin:k2c1ose 3gcp t 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.