97.01: A force F directed at an angle of θ fay9, jx)2hxp above the horizontal is used to pull a crate a distance D acrosjp29yf,) axhx s a level floor. The work done by the force F is

  97.33: A softball player caty2 3so2+ z,r1sjb ztj5rt* ofnt /ez(;oc3c toches a ball of mass m, which is moving toward her with horizontal speed v. While bringing the ball to rest, he+s co(*5cze2r1y3 ,nj3t;s2to otzt jo/b fr zr hand moves back a distanced. Assuming constant deceleration, the horizontal force exerted on the ball by her hand is

  99.14: A construction laborer holds a 20 kilogram sheet of wssvu(96m+1; mm npdmq0*ywi gallboard 3 meter above the floor for 4 seconds. During these 4 secondshow much power was expended on the wallboar u0mm 9dsm6sy+mpn1 q( vw*g;id?

  17.11: A 5.00 kg block slides 2vqw ; dvf,,;vpurz- wwith uniform acceleration on a horizontal surface for 5.00 s. The block’s kinetic energy strictly decreases from 50.0 J to 20.0 J d, fvwv2uz,w;p- v;qrin this time.
What is the average speed of the block during the motion described?

  17.12: A 5.00 kg block slides with unifmrn,bi2 p/ 4r3p cuy;jorm acceleration on a horizontal surface for 5.00 s. The block’s kinetic energy strictly2;m3b4n ir cppry/ju, decreases from 50.0 J to 20.0 J in this time.
Which one of the following choices best represents the magnitude of the block’s acceleration during the motion described?

  16.11: A 12.0 N net f/dev sv54 4 q7c8qdrnforce directed to the right is exerted on a 3.0 kg block for 5.0 s. The block was initially at rest and csn/ f4eq5 dd47rvqv8slides on a horizontal surface.
What is the speed of the block at the end of the 5.0 interval?

  16.12: A 12.0 N net force directed to the right is exerted on a 3.0 kg block fbmv 5g6g 2qervs8-k 0gor 5.0 s. The block was initially at rest angg2gr 56q v0b s8ek-mvd slides on a horizontal surface.
What is the kinetic energy associated with the block after the 5.0 interval?

  00.15: A student initially at reston a frictionless frozen pond iz .ppdf),u2 u;k0tlh throws a 1 kg hammer in one direction. After the throw, the hammer moves off in one direction while the student moves off in )t; d uf,0klih2pu z.pthe other direction. Which of the following correctly describes the above situation?

  03.14: A fan blows the air and gives it kinetic energy. An hour aftercxwlacpvav ts:,)g93 owqr;8r ,r *(e the fan has beens, 9gclr *;:(cwtexra3v 8rw)va p ,qo turned off,
what has happened to the kinetic energy of the air?

  09.05: At an instant, a block of mass 0.50 kg has a positiyd u(w+/ x ul 2ppi.yf/ sz4+v5vjax(yon of 3.0 m, a speed of pfujpy l+2s /y5d4xv+ i(.y xu(wa/vz4.0 m/s, and an acceleration of $1.0\; m/s^{2}$ . What is the kinetic energy (in Joules) at this instant?

  05.05: A box of old textbooks is on the middle sheldd2b ,6 hqjlkrw4 ir56f in the bookroom 1.3 m from the floor. If the janitor relocates the box to rw45d,66hbqk2 d lrij the shelf that is 2.6 m from the floor, how much work does he do on the box. The box has a mass of 10.0 kg.

  02.32: An automobile engine delivers 24,000 watts (about 32 horsepower)c)up/of:-psr of power to a car's driving wheels. If the car maintains a constant speed of 30 m/s (about 65 mph), what is tsu:p r- opf/c)he magnitude of the retarding force acting on the car?

  09.13: In the figure to the right, a box moves with speed 5.00 m/s at the botto1j09b l vr8enx gw2-ae o3zbr8m of a rough, fixed inclined plane. The box slides with constant acceleration x38e8 r-wn2 vbe rzlg0o9aj 1bto the top of the incline as it is being pushed directly to the left with a constant force ofF = 240N. The box, of mass m= 20.0 kg, has a speed of 2.50 m/swhen it reaches the top of the incline.
What is the magnitude of the acceleration of the box as it slides up the incline?

  09.14: In the figure to the right, a box moves withzab +slt8pn e4;.3rwt speed 5.00 m/s at the bottom of a rough, fisl3arnt 8pzw.+ et ;b4xed inclined plane. The box slides with constant acceleration to the top of the incline as it is being pushed directly to the left with a constant force of F = 240N. The box, of mass m= 20.0 kg, has a speed of 2.50 m/swhen it reaches the top of the incline.
How much work is done by the applied force F to the box?

  11.30: Two cars travel to the right, each starta ygbjjc z+w(v :(gl1 kxs pe.r5rw9tqdj48.+ing from rest, along a straight road. CarA has twice the acceleration of Car B. After traveling a distance F, Car A has speed B. When Car B has traveled the same distance F, what is its spt .r+gxy9.:a5pvw 1r4 kw +qg8zcldsj(j b(ejeed in terms of B?

  12.07: What is the net force acting on the object during the time interv5*z )zs-x ,id.8skpz oemg im/al of the accele8oxs5zi.gz- p *,/dmm zik)seration?

  12.08: Through what distance does the object move during the time interval of0 +0:xozek0pwz t(aug the acceleratio0a+ep0 wx0k zuzg ot:(n

  12.19: The magnitude of the linear momentum of a 4.00 kg point mass jdycphypop*sw/6 + -:is changed from 6.00kg.m/s to 14.0kysjd + /cwpph*:-p oy6g.m/s in a time interval of 6.00 s. What is the change in the kinetic energy of the mass during this time interval?

  14.11: A crate gains 36.0 J of kinetic energy whilbmz mf3/ .r*zae its speed is increased from 2.00m/s to 4.00m/s. Which one of the following choices best represents the mass of the m/m.3z *bz farcrate

  94.38: A force F at an angle θ above the horizv/mti9 t1b 0)3t*6bfrb-rsvw t c3hqaontal is used to pull a heavy suitcase of weight mga distance d along a level floor at constant velocity. The coeffi1st 6ttm30fw r t3*bb vh )ai-/r9qvbccient of friction between the floor and the suitcase is μ. The work done by the frictional force is:

  14.31: A toy crane exerts an upward force and deli- yfg(79/9 nsux+zw;f0kir -tgslol bvers a useful power output of 0.10 w to raise a block vertically at a constant speed. At what constant speed will this crane raisg +l i-klz 09;rgftw 9/7s x-ynuso(fbe a 0.20 kg block?

  12.18: A 1.00 kg object is released fr)guk )n1ae/z3zt,ea c om rest near the surface of the Earth, the gravitational force acting on the 1.00 kg object by the Earth does 10.0 J of work on the object as it falls 1.00 mto the ground, which one of the following choices best represents the amount of/c) g kzz3,taanu e)e1 work done by the gravitational force acting on the Earth by the 1.00 kg object during the fall?

  96.18: A rubber ball is held motionless qsm79jm ju6s; jbjv/15n9 4aru5s upka height ho above a hard floor and released. Assuming that the collision with the floor is elastic, which one of the following graphs best shows the relationship bsr 4m /jvj7 165;mss95ajjuuu 9 pqnkbetween the total energy E of the ball and its height h above the surface?

  07.06: A 500-kg car is qkmbbx2v23 d3v;pn m6 ;ogw w02x)ibymoving at 28 m/s. The driver sees a barrier ahead. If the car takes 95 m3qmb pi;2yd 2;wwg0nv6x3bmbk2v xo)eters to come to rest, what is the magnitude of the minimum average net force necessary to stop?

  00.26: A 500-gram ball moving at 15 m/s slows down unifo3;k oa l50wr k6vq0kwfrmly until it stops. If the ball travels 15 meters, o akf0wkkwrv;l6 530 qwhat was the average net force applied while it was coming to a stop?

  02.26: Consider two laboratory carts of different masses but identical kinet l i .6u 29lwn.ggva)vq;0+ xgu:xbnimic energies and the three following statements. Which of the above statements would be co0 .l.b :2qi wia gm6x9;lxuggvu+v)nn rrect?
I. The one with the greatest mass has the greatest momentum
II. The same impulse was required to accelerate each cart from rest III. Both can do the same amount of work as they come to a stop

  06.19: A 60.0-kgball of clay is tossed vertically xd-s m/b9q r(g w.jy)sin the air with an initial speed of 4.60 m/s. Ignoring air resistance, what is the change in its pote9mw(yrb j-sg/)sxq. dntial energy when it reaches its highest point?

  06.20: A boy jumps from rest straight upward frocmvt7q g/n3 9km a flat, stationary concrete surface. The boy, of mass M, leaves the concrete surface with speed v and his center of mass rises a distance d to the highest point of the motion. kmcnt9 vg37q/ How much physical work did the average normal force of contact (N) between the boy’ s feet and the concrete do on the boy?

  02.48: An object of mass M is dropped9k ;ols4 ze3w:cr /el) c3(1ssxzmode from aheightH above the ground. The object crashes into some soft earth and comes to rest by compressing the earth a distance of H/2. Assuming that air resistance is negligible, what is the magnitude of the average constant force exert o)9xzd;ek c (/rlosswc4e1sze 3m:3led by the ground on the object while coming to rest?

  12.48: An object of mass M is dropped from aheight H above the . mv2rhfr9f4ocff4l 4o(zy7 gground. The object bounces off of a horizontal surface in a collision lasting time T. The object then rises upward to a maximum herzvm( o27fo cf94y44 gfhl.rfight H/2. What was the magnitude of the average net force acting on the mass during the collision with the surface?

  96.38: A pendulum bob mass mon a cord length L is pulledpugt0y 6v c-f8 sideways until the cord makes an angleyfvc6t8u- gp0
θ with the vertical as shown in the figure to the right. The change in potential energy of the bob during the displacement is:

  03.49: A sled slides up a uniform incline of unknown angle. The sled,du3k0g15umnq* mw ik 0- z*wco which started at the bottom of the incline movin01d3* -gwomq n *ukcm5izk u0wg at 10.0 m/s, rises to a height of 3.30 m above its starting position and momentarily comes to rest. The sled then slides back down the hill. What is the sled's speed when it returns to its original position at the bottom of the hill?

  06.09: A deliveryman moves 10 cartons from the sidewalk, along a 10-meter rafew2rsl f1)m wh m0v;5mp to a loading dock, which is 1.5 meters above the sidewalk. If 1;2l vse0f5h rm mwf)weach carton has a mass of 25 kg, what is the total work done by the deliveryman on the cartons to move them to the loading dock?

  12.16: A constant force )bp )mq5pn.0n4zktb kF=50N (as shown in the figure) is applied for the 6.0 meter motion of the box upward along the incline. The mass of the block is M=15 kg. Which one of the following choices best represents the work done by the force F onqkmn tb kp)540b z).pnthe box for the motion?

  04.48: Two identical bowling balls A and B a;c 0tep*m.k czre each dropped from rest from the top of a tall tower. Ball A is dropped one second before ball B. After ball B is dropped but before ball A strikes the ground, how are the mechanical energies of the two balls czmpt0* c;e.kchanging?

  11.28: A person throws an object of mass M straigjnh z+w8sel2 1ht upward with an initial non-zero speed v. The object rises to a maximum height H above the e hz281s+j lnwlaunch point. The person now throws an object of mass 0.5M straight upward with initial speed 2v. In terms of H, to what maximum height does the object of mass 0.5M rise above the launch point? Ignore air resistance.

  96.20: A force of 10 hq6j+.dkv /. aeswz mwmy 20j0N stretches a spring that has a spring constant of 20 N/m. The potential energy stored in the spri 2ae qwkj.s/ vz6+00dymw.jmh ng is:

  97.10: A compressed sprinsrlq)xykn tjxx;af21yc qa877r sd.3o* h, l3g has 16 J of potential energy. What is the maximum speed it can 2x qn joq tsy8ll7;.d) 3*,kfxrsyraah7x1c3impart to a 2.0-kg object ?

  

  10.31: An object of mass M starts from rest sl -v( ;k/uchoat the bottom of a fixed incline of height H. A person decides to push the object up the incline in one of two ways with an applied force shown in the diagram. In each of the trials, the object reaches the top of the incline with speed V. How would the work done by the person on the block compare -u/v;lcoh( ksfor the two trials? Assume the same constant non- zero coefficient of kinetic friction between the incline and the object for both trials.