97.01: A force F directed at an angle of θ yacnj79ga ,*,ub+ )jkvi,. mpewsrp( above the horizontal is used to pull a crate a distance D across a level floor. The work done by the fopy79w.)ueabksr jpmg j,,i an+(c,*vrce F is

  97.33: A softball player catches a ball of mass m, which isv,je9j 1f0w3hrab:/dacbd .e moving toward her with horizontal speed v. While bringing the ball to rest, her hand moves back a distancaaebedd:v j, 0hbr 3cj1 .fw9/ed. Assuming constant deceleration, the horizontal force exerted on the ball by her hand is

  99.14: A construction lw 3in/yl)+byzg o wr(1aborer holds a 20 kilogram sheet of wallboard 3 meter above the floor for 4 seconds. During these 4 secondshow much power was expended on the wallbowzn)y 1gr+w/i3( ylboard?

  17.11: A 5.00 kg block slides withx.lc 5pva- fx. uniform acceleration on a horizontal surface for 5.00 s. The block’s kinetic energlv xfcpa-5.x.y 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 acceleration on a h v3grqg)jo(c/orizontal surface fgq/r)cv(j og 3or 5.00 s. The block’s kinetic energy strictly 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 force directed to the right is exerted on a 3.0 kg *neyx d2zm :-ya.dx t*9n .htpblock for 5.0 s. The block was initially at rest and slide*pd y-nya d x.*m zx:ntt9.2ehs 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 directedhfw+fqcp/;vws9r 7 -j:eop *l :5yrzh to the right is exerted on a 3.0 kg block for 5.0 s. The block was initially at rest and slides on a horizon :yfwh;h7:p*r/jo-r5p 9vlsf e +qwcz tal surface.
What is the kinetic energy associated with the block after the 5.0 interval?

  00.15: A student initially at rm)vpm.ea,2s q fqd(j t4(qw2n,u h 3rjeston a frictionless frozen pond throws a 1 kg hammer in one direction. After the throw, the hammer moves off in one direction while the student moves off in the other direction. Which of the folloj(ms3v,q, )qef(u4qrn2. pwj2amht dwing correctly describes the above situation?

  03.14: A fan blows the air and gives it kinetic ene.lk,p stsj+c) rgy. An hour after the fan has been t sjt clk.+s)p,urned 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 oftoacuw02 ;. s7 vck 9gpmqse45 3.0 m, a speed of 4.0 m/s, and an accelerati;0se4ko2c9m 7 qac5wgvtusp. on 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 books h c*y.)x9-zgikc ax3room 1.3 m from the floor. If the janitor relocates the box to the shelf that zi3kac.y9h g *-sx )xcis 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 24,000jt,46nb;.aven9.2 q izqy 07afwhq yc watts (about 32 horsepower) of power to a car's driving wheels. If the car main40b2taew9n. ; zj7vihq,ay6 qnyfq.c tains a constant speed of 30 m/s (about 65 mph), what is the 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 8jxq-g7tzw g 2t78au9tlq 9 ujwmc( .wbottom 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 constanwg tuq7g.twcz8 9wju9a-j(82q7 lxt mt 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 g,.8u gq v-yqcxy/b;d5.00 m/s at the bottom of a rough, fixed inclined -,b;8yyq dvg/xqgcu .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 soi+ v2u1+t4+ zczkcu starting from rest, along a straight road. CarA has twice the acceleration of Car B. After traveling a distance F,iuso zz 4+++ckuc 1tv2 Car A has speed B. When Car B has traveled the same distance F, what is its speed in terms of B?

  12.07: What is the net force ac/8ru+vhthy( :nfa iuo:3 qka 8ting on the object during the time interval of the acceler:uvai(ht3:a h /8yo kunq+ f8ration?

  12.08: Through what distance does the object move during the time 7s yn*wi7nq-g,zsj.u l b- 6zliw7,vy interval of the accelerati67 zs-lbuqy wsy, iwvjn 7iz*. ,-7glnon

  12.19: The magnitude of the linear momentum of a 4.00 kg point masshk1a.nej dq)5aj ew(4qr- q5h b0ym:c is changed from 6.00kg.m/s to 14.0kg.m/s in a tim ed(m)h5c:kq j 4yeaa5h1 n0-j qr.bwqe 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 increasebeio1 ,kj0 4hof11(p y n2alrzd from 2.00m/s to 4.00m/s. Which one of the following choices best represents the masib ln1 (o1zykp1hfoj04,e2 ras of the crate

  94.38: A force F at an angle θ above the hp h gl(/jvs6tgl 9f;y:q9 ab.corizontal 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 flo.ljqsf9ga /blht(cg : p6y9;vor and the suitcase is μ. The work done by the frictional force is:

  14.31: A toy crane exerts an upward force and delck+1be2i* wnbivers a useful power output of 0.10 w to raise a block vertically at a constant speed. At what constant speed wib we2*+b1nck ill this crane raise a 0.20 kg block?

  12.18: A 1.00 kg object is released from rest near +qhi 3 v el2ov;0ayjb(the surface of the Earth, the gravitational foj+bv0 l(2y 3hvo; iaeqrce 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 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 m: tpm/(nd fm 5g5wi7zxotionless 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 the ball and its heig dn:(/ i5xtmgfm5zw7pht h above the surface?

  07.06: A 500-kg car is moving at 28 m/s. The driver sees a barrier ahexgf5kee b em)m;5s;q/2 ot b9gad. If the car takes 95 meters to come to rest, what is the magnitude of tge2km;g9/e5ms t)x;5 bob fqehe minimum average net force necessary to stop?

  00.26: A 500-gram ball moving at 15 m/s slows down uniformtr r+w ltl;6r6ly until it stops. If the ball travels 15 metersl;rt+l6rtwr 6 , what was the average net force applied while it was coming to a stop?

  02.26: Consider two laborator8t uggur+ l6q3y carts of different masses but identical kinetic energies and the three following statements. Which of the above statemen6+lg 3utq 8rguts 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 tosse e*vf)d0ib d w,gl5,nsd vertically in the air with an initial speed of 4.60 m/s. Ignoring air resi0vwsf dde* lgbn)5,,istance, what is the change in its potential energy when it reaches its highest point?

  06.20: A boy jumps from rest straight upward fropocw siig5j4;/y o3- mm 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. How much physical work did the average normal force of contact (N) between the boy’ s feet and-oi5w j ;opm/gycs3i4 the concrete do on the boy?

  02.48: An object of mass M is dropped from aheightH above the ground. h7/k lb)6sbkyrw:u+)v9zgngThe 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,7b9 yz kgk/)s6)u +lrnghwvb : 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. Thtz6 jh+wpzoo71fhz(9 e object bounces off of a horizonta(h9zh1zop6t7jwz+fo l 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 on the mass during the collision with the surface?

  96.38: A pendulum bob mass mon a cord length L is pulls4t3 ahm kwl5qj;+v /eed sideways until the cord makes ate/+a 5l4; hsw 3kmqvjn 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 unifo*5xxudls- 5,wd-nkv,sof wj3 rm incline of unknown angle. The sled, which started at the bottom 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 rdv*x55- s k ljuxs,3odf-w n,west. 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 :09s,i-wn6k+fyvg ) nudxzrw moves 10 cartons from the sidewalk, along a 10-meter ramp to a loadin06ywwzxu-rn, k d+sfg iv9n ):g 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 deliveryman on the cartons to move them to the loading dock?

  12.16: A constant force F=50N (as shown in the figure) is applied for t vnyh)g 4cq 1fwf +fz.5rnf,;ahe 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 ,+;y5qvn r f)1h.faf4zwgfnc force F onthe box for the motion?

  04.48: Two identical bowling balls A and B are each droppe r7gc-6um6rr)piqte (d from rest from the top of a tall tower. Ball 66cuqp) 7(egr-irmrt 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 changing?

  11.28: A person throws an object of mass M s 4psrtf i,nvnp/y, o/4jie+b6traight upward with an initial non-zero speed v. The object rises to a maximum height H above the launch point. The person now throws an object ov4r,ins pi,/6y t/e4n obj+ fpf 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 0yj1ya*0puah qk i g0tor+a vj(r28w8spring that has a spring constant of 20 N/m. The poua k 8ay*ow r0ygq a(1208+hrtjp0vji tential energy stored in the spring is:

  97.10: A compressed spring d5;7rsldybqd, n(hj+ g vj x)a(ij**xo p+.dohas 16 J of potential energy. What is the maximum speed it can impart to a 2.0-kg object ?dd+h+d5bjg7j(loj ;i.rp*vsn *xado)xy ( q,

  

  10.31: An object of mass M starts from rest at theiawig75nra9 ,l 3k2irfz7 u.g 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 in75.3nra7rfikg z u i,wg9lai2 cline 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.