95.02: An object shown in the accompanying figure moves in uniform circular 7 m)s9od);kkerw s-z1 kfgld.motion. Which arrow best depicts the net force acting on the object at the insdfsgrkm) 7s)z-k. e l91 dowk;tant shown?

  05.31: A child is belted into a Ferris Wheel seat that rotates counterclo1cu5:pv:2xb sz2+3htvxx cn f ckwise at constant speed at an amusement park. At the location shown, which direction best represents tx:z hv 53cs1fvxb:t p2nux c+2he total force exerted on the child by the seat and belt?

  08.14: A particle continuously moves in a circular path at qudo0,/x;7w)uu 1meby cgf- yconstant 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 arou7ydgfbcyu;0q wu) o ,x/m1-eund 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 speed int498*y ( gidk.fb xk*mbs. awb a counter- clockwise direction.ty8*g 9x .4abb(i skwmfd.b*k 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 sm4pmko,qdp3-+w aghd5l6,r nf0un/e rai5 (vertical circle shown. Which arrow besu56p(o0 lsdgm-,r/q,i 4wk pmefa+danh5 nr3t indicates the direction of the object’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a ( uqb(g3*udzc9 p0if ssmall 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 the point labeled P in the figure, at which lettered point onz90 3fpgu (*q(usdi cb the path should she let go of the string?

  15.23: A car moves with constant speed around a horseshoe-shaped p (c9 y4z2heabyazba+j18 b,nvath as shown with the arrowshja,z2 z+ ea94by8 nc(ba1bvy in the figure. 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 b6kf dt8uj 2.n d6z,toperform an experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in t8tjk.nbz, td2o66 ud fhe 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 fh zj4j g/anys()m0z3u07 kg lthe 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 0.80fhz )(3j0y j7n u/ak mgg4zl0s. What is the magnitude of the force of friction acting on the object?

  07.19: What net force is necessary to keyf94/gx giu7oep a 1. 0 kg puck moving in a circle of radius 0.5 m on a horizontal fri74yx i/9gg ofuctionless surface with a speed of 2.0 m/s?

  05.03: What is the centripetal acceleration of an object (mass = 50 g)nhj fkdgo1 s;p. .xaiy .e29r; on the end of an 80-cm string rot1xfdy2.shop9;keijn ;ar. g .ating at a constant rate of 4 times a second?

  09.24: A point mass moves along a horizontal circular path aii(d :5jc* b cv3yvb-of radius 0.8m with a constant kinetic energy o* id-cj a5vbvb(3yci:f 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 whirled in a hog;k.tbesfw- a i5 +9e5in 4epvrizontal circle at a constant ;9p5b-tnefg4+ieak. e5is wvspeed 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 /fe64 olt )z 9v(ns+*umgdtenwhy0z,end of a rope, in a uniform circular motion. Whiz(lvofhust n+, w)6 ng */te4 0y9ezmdch of the following statements is NOT true?

  00.19: An astronaut in anjx8m93 qo8t+)f hep tm orbiting space 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 tension in the string is F. If the mass, radius, and speed were all to double the tension required to maintain uniformqj +3t8me f9x8 ho)tpm circular motion would be

  07.22: A mass m is pulled outward until the string of l sv3/ywjk/p*length L to which it is attached makes a 90- degree vk/jp/ *sl3yw 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 bottom ofthe arc?

  94.15: A car is traveling on a road in hilly terrain, see figure to the i0s2(+iytqinp* + ths l5bl(t right. Assume the car has speed v and the tops and bottoms of the hills have radius of curvature R. The driver (btsty +tpl0qih2 lsi *5+i(n 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 6o cqw1 50eccpthe 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 represents the magnitude of the upward force exerted by the road oq61occw50e cpn the car?

  97.13: A small sphere is moving yq9a1)1b4 c6wr65 eux qzqbpx in a vertical circle at constant speed. The magnitude of the net x ub1cez49 6bqqq)x1 arw5p6y force on the sphere

  11.47: A simple pendulum of length Lhasa p/ 0db*yxqdy6 epf6zj2oint 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 odye2 b/xqzyf0 jdp*66 f 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 string forms a simple pendulgf-+6wrrgr m+e34ri5 q dyo tai9cv1 0um. 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 thr9rrg- w6y r0qfg3 toe+4+ rmiv1d cia5ough its lowest point?

  04.41: A centripetal force of 5.0 newtons is applied to a rubbe(, j,srjlo d9khg)s(qr stopper moving at a constant speed in a horizontal circle. If the same force is app (l), gj(,s h9rqojskdlied, 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 suo,5)a7 d47sizowmyp3 j*x ijwt7m0 gvrface, connected to an ideal horizontal spring that is upstretched. A person extends the sprinta7jdmso07iw,y4 3z*p xoim) jw7gv 5g 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 w-9bh(w /39wv-9xwxtr7c nv fv b/kl dmass with a constant speed of 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acwvwd 3w9(/bc/rx9w-vhk97t -nbfxlvting on the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (k 9t)cr.hm5r v bkq(bj+e q1f ,3pqy:qvkdc/-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 o9 c.j)1r-( kqfmtvqrq+vy/ c5 bq,k edkh:bp 3f 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 rrgi);g6qb4 xrj d* k f03b-wsto the end 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 o*d0fjgrb; 6-)qwig4rsbxk3rf 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 m frfex u xh,4nkfa54(,otion as shown in the figure. The string to which the mass is attached has a length of L = 3.00 m and a5 ,f,kx(hue r4f4x nfforms 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:qdw +d2u.tpa7 nkou0l,f7uq 30.0 cm from a horizontal disk’s center. The disk starts to rotate from rest about its center with u7 fk2d0, pun uo+wqda7l tq:.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 i4ik 99exs+ xs9,ywcyns attached a distance R =1.75 m from the fixed center of a disk as shown in the figure. The disk s+sxwysy, 4 x9ki e9n9ctarts 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 inhnjp)x *dg:*32 n ldux a circle, starting at the top, with initial speed 17.0 m/s. The object’s sjld3x*2g*nn:uhp xd ) peed 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 final speed of the object?

  16.40: An object move:o ,kq* khznx7s in a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increaskzh*:x , n7koqes 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 b d6ne6ayrzelf :ixw*poh1 5( 0lock rests at the bottom of a bucket. The bucket is spun in a vert6w0 hor*56z l(dnei:ya x1efpical 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 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.