95.02: An object shown in the accompapo 7v -dqkjpkv4 -ye0 dwo:of5.g3q+vnying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object at the instafd:4oqj v3v+qe7oy.50pkwd-p kog- vnt shown?

  05.31: A child is belted into a Ferris Wheel seat th:yp-q7js1pe+:d ,xy tjkihuo1(k+* ck ae;kbat rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represen pe kpc1iket-(*kk uy sq;ao+hbjj+ ,y::dx17ts the total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular as3g ;x f rl(4l8 x;e4-a ;/ qjemvmgqqp,dj.qpath at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along t 43/s;l e,v4laf. 8jq pja eg;xgrxdqm-(;qmqhis 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 velocity during this time interval?

  08.15: A particle continuously moves in a circui(2.m5 g pemok4(p*q- avr;je6n ymkclar path at constant speed in a counter- clockwise d.ekpm n (qymc5 g*ov4ea6;(2j- kpmirirection. 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 the vehmtt57p/cb t: - qzq hx-rx14p2yknp :bthc;4rtical circle shown. Which arrow best indicates the direction of the object’s instantaneout zqt;: :t1bx5tb 7c/pn-44pxy- qkpc2 rh mhhs
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connectei 9:k omh gqy2xl20(usd 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 the point labeled P in the figure, at which lettered point on the path should she let go of the struqlx y(:gohmi0k2 2s9ing?

  15.23: A car moves with constant speedr;jn ;g 6pctuk,y,km7vsj x ;si6m/ h8.qqvs ) 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 car in travelin r/vtmqpuv,j)si q;cmx, 6 ;y 6k gss7jn.8k;hg from Wto X?

  08.35: Astronauts on the Moon p1d rqjyn5vc2 9erform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment sdn591rjyv 2cq hown 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. k9wpc05pc9nu 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 ki09wp9c5 up ncknetic 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)-2idlw 5 r h4avpyou6v,uf2f(su,i q 1. 0 kg puck moving in a circle of radius 0.5 m on a ,vu qdru 42sva5-fupw(l, ii6h)fo 2yhorizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 g) o6qhmn 6l9hr o+n the end of an 8l+ hmq9oh6 6nr0-cm string rotating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontalv3l9:sw ap cfu)p +nh6 circular path of radius 0.8m with a constant kinet)w36an:pc+vhf lps 9 uic 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 and 8:ajf gk(ltz sx q6ighq 2px78h t0k+0)rbg/lwhirled in a horizontal circlsg /tf)pgb : 0kx 0ht7xzlr 286k+hlq(i8ajgqe at a constant speed of 6.0 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 ukr ex0u.qr*d h/4p *erniform circular motion. Which of the folle*kh./ qe40 u* dprrrxowing statements is NOT true?

  00.19: An astronaut in an orbiting space craft attaches ah(e.o,v cvf:1awn(gd mass m to a string and whirls it around in unifw,1cnv : dg(he voa(f.orm 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 until the stz 9m0ewf qdy;jqa6f 0sut-(nxay20r8ring 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 through the bodsa9wxy0-zj0r28(0mfanq;uf 6q t e yttom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figure to the rij ugw2kof:ae*mv:m62 h/ mu2(x4 adv xght. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. The driver of the carda(memxfa:v2xo 2 :4m2g 6*hw u vu/jk is most likely to feel weightless:

  17.10: A 2000 kg car moves over a hill at a constant speed of 12.wb.+( ;xx8hrsh yux x/0 m/s. At the very top of the hill,x +x wbs.uyhh;/r8x x( 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 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 cob ;xfmqf0tcl5 0jf86 ynstant speed. The magnitude of the net force on the sphf ffyq;x05j8 m6b0 tclere

  11.47: A simple pendulum of length 9bfyn8srr9; ysp4w 71 ywnt3aLhasa 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 gravitationalsf7rb39t8ay nrwpys4nw 9y1 ; 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 st2-hh mxhk,6y fow sw -am)f1t6ring forms a simple pendulum. The mass is released from rest and undergoes simple harmonic motion. Which one of the follaoh h)hsf6m-ww- 2t1 6mfx k,yowing 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 point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubber stopper qnm meqb+lu ymc:-n73 3;nr h,moving at a constant speed in a horizontal circle. If the same force is applied, but the radius is made smaller, what happens to the speed v, and the frequenc,:+q;n 3 hern-l3nuybm7cqm m y f, of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface,wn z6f pbwgt:rc3t0c4u0*3 sa connected to an ideal horizontal s :cz3gnf 0c40*pru6wab swtt 3pring 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 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 a v5gkt yzl8605,o;e . rxd1ov.q zgms tcertically-oriented circle of radius 0.75 m. What is the net force actield.65oz 5x1;gst. 0q,gr om8y z kctvng on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins fyz 7/( 9lq.uhn kg/yp(labeled 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 center of dy/7ulh qkgf /.yp(nz 9isk 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 dt i.:1h,wegt (wu9,zl0zvbdend of string 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 2.50 m and forms t u(:h ,1t,09dwvzwz.gle i bdan angle of $θ$ with the vertical. What is the tension in the string?

  17.26: A 4.00 kg mas b;7t s4pvetspk9;u u9s is in uniform circular motion as shown in the figure. The string to which the me9k;;9b7t vp sutp4 usass is attached 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 masimym98-29j - q9a d ihs/zg. j/pwrq,v1uzzzvs 11.0g is at rest 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest aboutq8g199pizzrvmu zjh,//smz9 .j- iwa2- yqdv 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 distanc/on8i/fd 7 xrxe R =1.75 m from the fixed center of a disk as shown in the figure. The disk starts rotating from rest witdx78n i// xfroh 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 initial.b, 6rln5 :xw q0bqvyn speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an60 : lqb,b nnyqx.rv5w 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 9:h w gie4h/k :xmvnzf ii04.ia circle, starting at the top, with initial speed 17.0 m/s. The object’s s 4w/ifin:m : v0g.9ikxh zieh4peed increases uniformly 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 rests at the bottom of a bucket. The bucket is spuc k l6kpv (r9l)lz2cl5n 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 is at an angl5kv p296rclk llcl)( ze $θ=30^{\circ}$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.