95.02: An object shown in the accompanying figure e e5k35jc mvu+kfp;e- 8,gl7q m j0hag:zqwk6moves in uniform circular motiu am+k:-6mj5ve70 , ;k3cf kjph8qelq5egwzgon. Which arrow best depicts the net force acting on the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterm8vw)cscfzrr,bj/f2a14 8ns8w q / jiclockwise at constant speed at an amusement park. At the location shown, which direction best represents tzv8 jb1qf sm wjrn/88/ fa 2c,cws4r)ihe total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular path at constant speed in +cr )0uo(*cglm+htli ; tcwt8a counter- clockwise direction. Consider a time interval during which the particle moves alongcgh m +i8cl(wcl o+t;t*u)0tr 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 velocity during this time interval?

  08.15: A particle continuously moves in quf1. w:ffyn ;tk2k(v a circular path at constant speed in a counter- clockwise(nfk2 ut:v;q f1k. ywf 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 clockwise with constant speed around the vert 5 gr8ui5ht;dwical circle show i;w rdht55gu8n. Which arrow best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a s 8h ge79dw/gjcmall mass connected to the end of a string counterclockwise in 8dhc j /ewg97ga 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 string?

  15.23: A car moves with constant speed around a horseshoe-shaped path as u3ake7(rpgi,zl 0t9amiect:) o egu(x +w ( 7rshown with the arrows in the figure. Which one of the following choices best describes the direction of the average accelera z7xa e9ep70w+,i ):lgimrr(tkco u a tue(g3(tion of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an tjps4w d53jwco6hi : wafb bo++51hi, experiment with a simple pendulum that is released ffwwsbw:h+d5t1 +5,j a4jo3bi 6cphoi rom the horizontal 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 + 2ty.n p4fwnr6ct(c ucenter 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 is the magnitude of the force of friction acting on the object(y2+nr.nf4tuccw p6t ?

  07.19: What net force is necessary to keep a 1. 0 kg puck movingpw.jdgk; r 5,*6wpu8ke*xnug in a circle of radius 0.5 m on a horizontal frictionl;ep*ukd6wu. 5,p*k8rg wxng jess surface with a speed of 2.0 m/s?

  05.03: What is the centrip 1,*mfpl:dns2vm g4gd etal acceleration of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 times a secon,p 1g4ds*2ndm fvml:g d?

  09.24: A point mass moves along a horizontal circular palm8wm4y ;med y:6utv 9th of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of th mud 9ywlve4m8: ;myt6e 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 whirl(keq -zw + hmnaw-fx9)ed 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 revolution is:afm+znh-)( - q exww9k

  99.22: A child whirls a ball at the end of a rope, in a uniform circ;u. e2fneq r*xular motion. Which of the following statements erx f2e* ;qn.uis NOT true?

  00.19: An astronaut in an orkw(d; j pqne)3biting space craft attaches a mass m to a string and 3eqd(p n; w)kjwhirls 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 until the string of length L to which it is ,*qhikpiu +p z969z jxvc2d.x attached makes a 90- degree angle with the vertical. The mass is released from rest and swings throughh69zpqc9v u,ik. z+jixdp2* x 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 a road in hilly-7lnw 6di-marhz vp k, ml;9bm1.al5gv4a. ux terrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the a-6uv -x4, lnpk.b wgmdi.vlh a9l az;51r7mmhills 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 conswnswek1 nw4.r+l*gt h64e0 ks tant speed of 12.0 m/s. At the very top of the hill, the shape of the road can be approx6ns h4s* t e0 wlg.wkerw+41nkimated 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 isnripe(: :hs1:beh8* jnph kh 7 moving in a vertical circle at constant speed. The magnitude of 1h h p*i7hp:eknrsejh8:nb (:the net force on the sphere

  11.47: A simple pendulum of length Lhasa point m;u 7*gn)lsykx ass 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 w)xgsn l ky7;*uhen the mass swings at the bottom of the arc (point P)?

  16.32: A mass connected to a td - y1yl*zclge *c6p3string 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 point?*-pg3dyt 6zcl*e ly 1c

  04.41: A centripetal force of 5.0 newtons8 7njfhd6uq 9,gu r8hi is applied to a rubber stopper moving at a consta h du8fq89hr 7g6niju,nt 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 frequency f, of the stopper?

  05.28: A mass, M, is at ed9: s)0 braldrest 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 by the person to hold the mass stationarylbad9e)rs0d: there?

  12.22: A girl swings a 4.0 kg mass w:f*.o *tsgln*vl a hf+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 ihf *t*v .ols*a nlfg:+t is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X andY) are 7yigax*lx;/ b6oymm * 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 disk *y/67oxmxyg blm i a*;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 euubh c1bfide-88mz- v6pt p3 +te5 ;hg80wkfznd of string and moves about the string’s fixed end in a conical motion with a constant speed of 4.0 m/s. The 8bc5fee3i1 k88 hpb tmt-v;zw + fd-pzug0h6 ustring 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 inyuf ylh,hp2wx(t*. 5 o uniform circular motion as shown in the figure. The string to which the mf.2(h whu lo*t5, pxyyass 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 objectosb0(w86 qzlsrino bo : j1j+- of mass 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 constw:01 joo8b6+nbl o irsqjs (z-ant 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 mm e;u z mm.cjhlfb 88p)aojj+2)0y4q f/gmm-a from the fixed center omh;m a-8fl o+042 em q)8mbj ymg)juj pacf/.zf a disk as shown 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 cisfp5sp0h(a* /g 27/oo nl rhwwrcle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise through an angleoww5 nfpahs(20 /p*hl /rsg7 o 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/5x(8vi r fr.gqd 5apf top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved cafi5fgrxqv d(r5p. /8ounterclockwise 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 buckebz+ulkk,i9 8l ;lue,092zn 3jmih qwct is spun in a vertical circle of radius L by a rope. When the bucket reaches the highest point in its motion, it moves ,8lhlebqn+lm;3kw9iz zj, u9ku ic20just 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.