95.02: An object showw8rv 3kd -zh8in in the accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on hzwd 3ikr8 v8-the object at the instant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates h2ol:9j (sfr t0o rl9p+jl g0xcounterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the child by the se(fl9t2po l+ :9x 0lj 0orgshjrat and belt?

  08.14: A particle continuously moves in a circular path at constant speed in aw 8.m5 ,a (ukqcsu+axbtix5g( counter- clockwise direction. Consider a time interval during which the particle moves along this circular5su8mubcat . , +( g5(xkqwaxi 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 con,d9 -obkyhj7f tinuously moves 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 around the ch9 oj,7dy-k fbircle from Point P.
What is the direction of the average acceleration during this time interval?

  15.07: An object moves clockwise with constant sp1 b208l ggeqh0us *n6m- xikfkeed around the vertical circle shown. Which arrow0g*8 kg sl0 f6m-h1uxbk iqn2e best indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the end ofrsv1nj( s97n sywyb/ * 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 ofvny/* w9n(js s1s r7yb the string?

  15.23: A car moves with constant speed around a hoicu),fpa4f cm k+1 9op,uzwk ,rseshoe-shaped path as shown with the arrows in the figu9c,w,za1+uk i ) ppfucf4m,okre. Which one of the following choices best describes the direction of the average acceleration of the car in traveling from Wto X?

  08.35: Astronauts on the Moon perform an experimentkfhe3 d*s4t,eyti7 9r with a simple pendulum that is released from the horizontal pos d7hti,eskf3*e y9r4t ition 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 fro ykhy;1pvu5/rm 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 0.50, while the coefficient of static friction is 0.80. What is the magnitude of th15/yrhk vuy ;pe force of friction acting on the object?

  07.19: What net force is necessary to keep auosw zcpl7vt4 i+948a 1. 0 kg puck moving in a circle of radius 0.5 m on a h7wlza4uv 98 +csotpi4orizontal frictionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleratioagba)- 7)o9c3ylvzvfi8 txy*n of an object (mass = 50 g) on the end of an 80-cm string rotating at a constant rate of 4 times a second?itafy-lczb3o)av 9g8y* x 7v)

  09.24: A point mass kgd04kct4, xd 8d2wygmoves along a horizontal circular path of radius 0.8m with a constant kinetic energy of 128J. What is the magnitude of the net force acting on the mass as 28w4 gd4tkg0ky,xd cdit moves?

  96.24: A 2.0-kg ball is attached to a 0.80 m string and whirled ixvu8z 7g)3 qspn a horizontal circle at a constant speed of 6.0 m/s. See figure to the right.vsq )xgz up387 The work done on the ball during each revolution is:

  99.22: A child whirls a ball at the end of a rope, in smtf,oo.* q3ha uniform circular motion. Which of the fo*ho3.moqstf ,llowing statements is NOT true?

  00.19: An astronaut in an orbiting space craft attoqiwlz5+ui 7m l yb1p29zn1p 6aches 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 inlmbp6 +715iowl y z1ni pquz29 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 toc 2 e./anp-gkl 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 n le. 2/pakgc-string when the mass swings through the bottom ofthe arc?

  94.15: A car is traveling on a road ex8/w)bicu h6 in hilly terrain, see figure to the right. Assume the car has speed v and the tops and bottoms of the hills have radiu c )i6/8ehxbuws 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 12.0 m/s. At 9t /f/ pdfgi+nthe 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 following choices best represenn f/ /i+tg9dfpts the magnitude of the upward force exerted by the road on the car?

  97.13: A small sphere -gdvk t5usa:3is moving in a vertical circle at constant speed. The magnitude of the net forcek-d5us vg3:t a on the sphere

  11.47: A simple pendulum of length Lhasa point mass M released fromw7z0tnd/6kxz 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 frtz7 kz0dnwx/6om 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 connected to a sth bn 7hsc,.rn8ring 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 7n ,rb.s hnh8c(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 stopruwny0nz3n3mqgl.g3 9no3 x5per 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 frequency f, 3n gnrx o n w9lzqy.3mu50n3g3of the stopper?

  05.28: A mass, M, is at rest on a frictionless surface, connected to yb;s7 l)4dcttln8+2rprv po8 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 masp2 ;npvbro7st8 c +8)yrd4ll ts stationary there?

  12.22: A girl swings a 4.0 kg mass with a constant speed of 3.24 m/s in a v f-c3il4gjcn8p e4x- hty(e3xv)x0qherticc0v44t3-) xj q xc3ligh 8-ehnyxepf( ally-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 circle?

  14.23:Two small identical 0 hv a7jr(d*k,ue /mcgcoins (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 distav *edm0/aj 7uh(crgk,nce 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 of string and moves about the strinj mncsbr*nc6q-ty.j3)k )8d1jswmz , g’s fixed end in a conical motion with a coymqbs)k* crdsn. j,wj 8 )j361-ncmztnstant 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 showro r5mn.deo8 7m hl+a)n in the figure. The string to which the mass is attached has a length of L = 3.00 m and formm.ah re5 +7no 8old)rms 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 c3i i:w / 1tqbujtae2etm q4r4:m from a horizontal disk’s center. The disk starts to rotate from rest about its center with a constant angular acceleration1iq4tet 3rw ta :2uq:j4be i/m 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 di6,fg7c i/oky gstance R =1.75 m from the fixed center of a disk as shown in the figure. The6kgcfo 7 /igy, 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 circle, starting at tdc ymztku1b )ns1y+6/ he top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has moved counterclockwise ths6 bz1d+ y/nk )y1tmucrough 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 top, with initial speed 17fj*i sh44 yr+b.0 m/s. The object’s speed increases uniformly until it has moved countercls44bh* f+jy riockwise 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 buckei3sqg: 21l nr l*7lho0;ucoto t is spun in a vertical circle of radius L by a rope. When the bucket reachli;slo*3:c 0 qgr ol no2h1u7tes 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 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.