97.01: A force F directed at an angle of θ ab ,3b hvz,)b)qir +:9xg ,xaziaps.jxsove the horizontal is used to pull):b.qaz,xpx+az,9 rs,ivi) s bx3hgj a crate a distance D across a level floor. The work done by the force F is

  97.33: A softball player catches a ball of mass m, which is kio igms3:t :0moving toward her with horizontal speed v. While brios 0 :m3ig:iktnging the ball to rest, her 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 kilogw pqvoy(/ ea4-qd4c3mram sheet of wallboard 3 meter above the floor for 4 sec-(w43eoqap q/yvm4 dconds. During these 4 secondshow much power was expended on the wallboard?

  17.11: A 5.00 kg block slides with uniform acceleration f my,2g6tdnt6*l hug; gyi) m)on a horizontal surface fotm 2)gyd*i,lu tmygf6h)g;6 n r 5.00 s. The block’s kinetic energy strictly decreases from 50.0 J to 20.0 J in this time.
What is the average speed of the block during the motion described?

  17.12: A 5.00 kg block slides with uniform acceleratio)pt4l z3 zafs/ :pz5rqn on a horizontal surface for 5.00 s. The block’s kinetic energy strictly decreases from 50.0 J t:szpaz/ 3 q 4)ltprz5fo 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 force directed to l8)hrihwqhwn jx t(55a w41y0 the right is exerted on a 3.0 kg block for 5.0 s. The 51hrhw0jl(t a)qy hx4 8wi5nw block was initially at rest and slides 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 twms. sf)y*,f for 5.0 s. The block was initially at rest and slides on a horizontal sff.*w ymts,) 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 throwsit/hs*n )clwmil( (e2uy r;- v a 1 kg hammer in one direction. After the throw, the hammer moves off in one di(iuvtw/r*csmn;-) (lelyih 2rection while the student moves off in the other direction. Which of the following correctly describes the above situation?

  03.14: A fan blows the air7q a*c r/wif(p and gives it kinetic energy. An hour after the fan hrqf c( p*7/iawas been 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 position of l m2hbr1;jo o1:ch40q pba9ze3.0 m, a speed of 4.0 m/s,r:pqze2o ajcol91h4h ;0mb b1 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 shelf in the bookroom 1.3 m from4/r je4:gvwis the floor. If the janitor relocates the box to the sh / esi4vwj:rg4elf 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 y0ua1i, x5g m,hulvr;24,000 watts (about 32 horsepower) of power to a car's driving wheels. If the car maintains a constant speed of 30 m/s (about 65 mph), what is the magnitude of the retarding force acting on the cm1,rv;u,50 u ixylghaar?

  09.13: In the figure to the right, a boxhu. e w gu)paj0h-0,;tn:lmth moves with speed 5.00 m/s at the bottom of a rough, fixed inclined plane. The box slides wnlu.:w he -phaj0 ,;0mgut)ht ith constant acceleration to 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 with speed 5.aqg -x8e)ayx) yb: rd)00 m/s at the bottom of a rough, fixed 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 =-aby )8)a: qrx)exygd 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 starting from rest, along a straight p (7krvz 7lj8oh.t 74drc.zmrroad. CarA has twice the acceleration of Car B. After traveling a distance F, Car A has speed B. When Car47..pr77h rzdok lt8zc(m jrv B has traveled the same distance F, what is its speed in terms of B?

  12.07: What is the net force acting on the object during the timei w6//0wlcks61pqbf ;j mq(fmkoo z32jk10g j interval of the accelew2/0fbijl3q1o6f6 jk c (jpkqmk o s;/1gm0zw ration?

  12.08: Through what distance does the objecjkh.t d9ztz5-asw woc4l p53 5t move during the time interval of the ac4 535-wskzwthzt9ad. 5jo lpcceleration

  12.19: The magnitude of the linear momentum of a 4.00 kg point ma27 p fj h pb(hayut.ou4*;mi.xpj .h0bss is changed from 6.00kg.m/s to 14o0.hy. j.uft(ppj7a2hbi; 4mhxupb* .0kg.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 while its speed is increased * l il4*xzq/9+*ih ev f+pojclfrom 2.00m/s to 4.00m/s. Which onefz* p l/h4*vilq x9+jec+ilo * of the following choices best represents the mass of the crate

  94.38: A force F at an angle θ above the,x7j ym5yt6tz horizontal is used to pull a heavy suitcase of weight mga distance d along a level floor at constant velocity. The coefficient of friction between the floor and t t6myyzx,j 5t7he suitcase is μ. The work done by the frictional force is:

  14.31: A toy crane exerts an upward force and delivers a useful power outpumpixo; y:1 0-zc+.rye7 bhbrmt of 0.10 w to raise a bloc 0 ro7;1i.-zhyxybbe:pr mm +ck vertically at a constant speed. At what constant speed will this crane raise a 0.20 kg block?

  12.18: A 1.00 kg object is 5z 5rx79wdz2 if1tuvxreleased from rest near the surface of the Earth, the gravitational force acting on the 1.00 kg objw 1fi75dz2r95xz tvux ect 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 work done by the gravitational force acting on the Earth by the 1.00 kg object during the fall?

  96.18: A rubber balln3-bft bldsjmw4xk/a7.)/k x is held motionless a 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 between the total energy E of thmkw/b)3j. s x -/ftx7nakd4lb e ball and its height h above the surface?

  07.06: A 500-kg car is moving at 28 m/s. The driver sees a barrier ahead. If trql4ev g7 if5fmeo 8wgj q019.he car takes 95 meters to come to rest, what is the magnituve w7ero1.j g8qlmf0gq5i 4 9fde of the minimum average net force necessary to stop?

  00.26: A 500-gram ball moving at8r47dtq4qj dj 15 m/s slows down uniformly until it stops. If the ball travels 15 meters, what was the a4d7 q jqtjdr84verage net force applied while it was coming to a stop?

  02.26: Consider two laboratory carts of different masses but ident:gy3q su6ikg, ical kinetic energies and the three following statements. Which of the abou:,6kq gygs i3ve statements would be correct?
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 in the air with vq:* ou h+nltst*q,2gz i+p2jfg,r 0can initial speed of 4.60 m/s. Ignoring air resistance, what is the change +fqquth :tr 2gs+*,ic 2 *pzlv gj0,noin its potential energy when it reaches its highest point?

  06.20: A boy jumps from rest str4x s c;jj*vjj5qs,mb r kw+7fpza+/+v aight upward from a flat, stationary concrete surface. The boy, of mass M, leaves the concrete surface wixcwzv p jfv/7+rj4,b ss+j*+akm5qj ; th speed v and his center of mass rises a distance d to the highest point of the motion. 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 dropped from aheightH above the ground. T3qf /huub 9j1khe object crashes into some soft earth and comes to rest by compressing the earth a distance of H/2.jf9/kbq1hu3 u Assuming that air resistance is negligible, what is the magnitude of the average constant force exerted by the ground on the object while coming to rest?

  12.48: An object of mass M is dropped from aheight H above the ground. The objeg d+s( n lyg4l8bj-/qpct bounces off of a horizontal surface in a collision lasting time T. The object then rises upward to a maximum height H/2. What was the magnitude of the average net force acting jyg +d8-sp qb(n/ll4gon the mass during the collision with the surface?

  96.38: A pendulum bob mass mon a cord length L isuo; 3uk0 jl1yg pulled sideways until the cord maojl u1g03 k;yukes an angle
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 unknownn(xw80 zgme7v((jnl;;p/ app9 ikm/rjmoz ;b angle. The sled, which started at the bot(k/wl0 ;pnxzg 7jvm(/m ;;j rin zame 98ppob(tom of the incline moving 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 mov tgcdr 2e9xtv0 t gj. uyw65+wfyah9+9es 10 cartons from the sidewalk, along a 10-meter ramp to a loading dock, which is 1.5 meters above the sidewalk. If each carton has a mass of 25 kg, what is the total work done by the delivwhfd r9yc 5 +9e x.t j6tavwgu9g+t02yeryman on the cartons to move them to the loading dock?

  12.16: A constant forq d o61*t nmof 7z3scnz+19giyce F=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 tiy o cmg1s71t6nf3 nzodq+9 *zhe following choices best represents the work done by the force F onthe box for the motion?

  04.48: Two identical bowlig5e j 1z4yg09e7hros kng balls A and B are each dropped from rest from the top of a tall tower. Ball A is dropped one second before ball sz5 9jg1rge0h y oe74kB. After ball B is dropped but before ball A strikes the ground, how are the mechanical energies of the two balls changing?

  11.28: A person throws an object of mass M straight upward with aiy u3)m)lyz.5 8dkq byn initial non-zero speed v. The object rises to a maximum height H above the launch point. The person now thro5d k.3my)qzluy yb)i 8ws 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 N stretches a spring that has a spring constant of 20 N/m. toxym;z(.v 4 xThe t4xyo(.zvx m; potential energy stored in the spring is:

  97.10: A compressed spring has 16 J of poten2k cr/pt vudq,a3.,xhe17 caltial energy. What is the maximum speed it can impart to a 2ec,vukd/p ,lr.23qat h x1ac7.0-kg object ?

  

  10.31: An object of mass M startor)e dlr /knqg2 -*/igs from rest at 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 th*g) 2l d/re/kogqrni-e trials, the object reaches the top of the incline with speed V. How would the work done by the person on the block compare for the two trials? Assume the same constant non- zero coefficient of kinetic friction between the incline and the object for both trials.