95.02: An object shown in thewj,39i:guq *yixs*fd -j0r ed accompanying figure moves in uniform circular motion. Which arrow best depicts the net force acting on the object a qdid0jje*ri uw fs*y:9 g3x,-t the instant shown?

  05.31: A child is belted into a Ferris Wheel seat ))nc4i60qz1 zfliwe v that rotates counterclockwise at constant speed at an amusement park. At the location shown, which direction best represents the total force exerted on the child by the seat 01evwizzf)6 q)clni4and belt?

  08.14: A particle conb+14b/mhczd ktinuously moves in a circular path at constant speed in a counter- clockwise direction. Co+b41/mzb ckdhnsider 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 velocity during this time interval?

  08.15: A particle continuously mk6t0uwxo5cw/+b+ x m(gd lg,aoves in a circular path at constant speed in a counter- clockwise direction. Consider a time interval during which the particle moves along this++g(gm5w6a 0wcdx kxbulo/t, 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 spi yah/*qz8*ormgw z,6eed around the vertical circle shown. Which arrow best indicates the direction of the oboga *zm*6 rw yqzi,h/8ject’s instantaneous
acceleration at the point labeled X?

  12.11: A girl twirls a small mass connected to the en flghg-jvhy21*/,o gfd 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 inh1*fl,-v /oy2 hgfggj the figure, at which lettered point on the path should she let go of the string?

  15.23: A car moves with constant obz.0 4(0,w98tzb *qpupzw3koy0lx* yqh xokspeed around a horseshoe-shaped path as shown with the arrows in thepq3(k*kp yq4t wh,luo. *z bzowyx9zx0ob800 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 perform anouudj)cfiy 3c uvcv .9+r 811a experiment with a simple pendulum that is released from the horizontal position at rest. At the moment shown in tu9du oc3a81)+1vr cvcuij f.y he 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 frtd9y pg. 5*gzz r+;nwjom the center of a rough turntable as the turntable rotates. The period of the turntable's rotation is 5tzwgr;. ng +5p9jdy*z.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?

  07.19: What net force is necessary to keep a 1. 0 kg puck moving in a circle ) *kyg* r8jaou+e2ewr.uu- ls of radius 0.5 m on a horizontal frictionless surface with a speed of 2.0 ma*).+2el*uwkoejursr y ug - 8/s?

  05.03: What is the centripetal acceleration of ajsr(tc gznst(* gm3*y/owr6( n object (mass = 50 g) on the end of an 80-cm string rotating at a constant ratesmz6w ( /3yo*gsr *(tt(rcgjn of 4 times a second?

  09.24: A point mass move nub5xf5x8sm 6s along a horizontal circular path of radius 0.8m with a constant kinetic energysbm5 un 6f5xx8 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 attnrindz /5v*:bached to a 0.80 m string and whirled in a horizontal circle at a constant speed of 6.0 m/s. Seenb/5in*:d rvz 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 circular motiwwlfd e.4u9oczo0;8l xp4hg :l o8y* ion. Which of the following statemxl:of4; wog4l8 c.poi z h9*uedl0yw8ents is NOT true?

  00.19: An astronaut in an orbiting space craft attachez4cv/w 2.xs rj4:y+ y0t ergvgs a mass m to a string and whirls it around in uniform circular motion. The radius of the circle is r, the speed of tgg s:0xyce2 y+vw /t4rz. vr4jhe 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 pulh zn8-a3ds:o cled outward until the string of length L to which it is attached ma3d:a -8nhs ozckes 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 bottom ofthe arc?

  94.15: A car is traveling on a rc rkv5 npw9m*-oad in hilly terrain, see figure to the right. Assume the car has speed v and k r nvpcwm9*5-the tops and bottoms of the hills 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 cony+gy 7uis.f2u uq gm.m6 rvt4(fqe(- b(j1va vstant speed of 12.0 m/s. At the 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 mu-fyqqjv mbus(2(mf.7.yiagtg(1 e v6vru 4+agnitude of the upward force exerted by the road on the car?

  97.13: A small sphere is moving in a verti1.qhecg8 rs2a0mz9 3lcu*cxycal circle at constant speed. The magnitude of12xuc c*y l8 eas r9q0zc3hgm. the net force on the sphere

  11.47: A simple pendulum of length Lhasa point mass M re,k,xr/ .czi slnq3v3sleased 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 /vlk.zr,cn si s q3x3,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 string forms a simple pendulum. The y4o)k ljcl5-5t lgphufk 7*h9mass is released from rest and undergoeso7jpkyt5 -luh 5khc l)f4*gl9 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?

  04.41: A centripetal force of 5wis. wl8 l-djq.1tm;i0isxc 3.0 newtons is applied to a rubber stopper moving at a constant speed in a horizontal ciii.c0.;it ds 831wx ljs l-wqmrcle. 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 an ideale6j.po,9 11gn / spwckuq/ccy 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 app 6c/pn9e c/qwcoupjgsk 11.,y lied by the person to hold the mass stationary there?

  12.22: A girl swings a 4.0 kg mass with a constant speed outqc.tqn30+m 9wggmko2 1doh yr)2 i 7f 3.24 m/s in a vertically-oriented circle of radius 0.75 m. What is the net force acting on oor3. qy +h7nk2 10dwgucqmt29 mgt i)the mass when it is at the lowest point of the circle?

  14.23:Two small identical coins (labeled X an2 0sdqx5ts*v udY) 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 disd0 x2qsut 5*svtance 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 t;p dw/cjb;e mjh+9n /and moves about the string’s fixed end in a conical motion with a constant; eb9pt j+ j;/nhdcm/w 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 cqi f da ty4+/.3h(wo7ae1wslkircular motion as shown in the figure. The string to which the d43 l iwq(tw fe.ksy+17ahoa /mass 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 mass 11.0g is at rest 30.0 cm from a horizontal diaa+ onc;5 ;kqvg wm 7(1 1oro1l5nszrysk’s center. The disk starts to rotate from rest about its center with a constant angular nwk 5m g vo(a 5cq;n+zas1ro7yrl11o ;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 distance2nxb zofo,hdks.7 a(mgs .b +t4f2 ,pm R =1.75 m from the fixed center of a disk as shown in the figure. Th2f(bh. mnxom4 stf, pogd.k,a z 7+s2be 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 movd vea5dr1li(5l744gu- wvcvbes in a circle, starting at the top, with initial speed 17.0 m/s. The object’s speed increases uniformly until it has movedr4wa15e- glb dcv d(l57v4ui v 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 top, withb-c dht 9dt.-gob 2uuwa+1f8 r initial speed 17.0 m/s. The object’s speed incrhbrau t9 tugdw-+od1. fb-2c8 eases 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 buckethme+ nvwp.1u75y4rk v8u -flikl 5os5. The bucket is spun 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 lynm v4- lu8i7vf5we+k srp 5huo k.15in 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.