97.01: A force F directed at an angle of θ above the horizontayik -8jjy)dx *tfwu/(qsk29 al is used to pull a crate a distance D across a le 9*dji a82/fywqyjsx()- ukktvel floor. The work done by the force F is

  97.33: A softball player catches a ball of mass m, w wdz 6a: )5olsiy-u9xehich is moving toward her with horizontal speed v. While bringing the ball to rest, her hand moves back a distanced. Assuming constant deceleration, the horizontallu5 z s:yiw6a-od 9x)e force exerted on the ball by her hand is

  99.14: A construction laborer holds a 20 kilogram sheet of wallboard 3 me/:8 yoojd9k doi g8a9mter above the floor for 4 seconds. During these 98:o/oad myk9 8j dgoi4 secondshow much power was expended on the wallboard?

  17.11: A 5.00 kg b8 fpbvu,m -)-0mdf nq:l zcb,p90ftmzlock slides with uniform acceleration on a horizontal surface for 5.00 s. The block’s kinetic energy strictly decreases from 50.0tm)flf8-0v:,n b0 b z9m dup,f-pcmqz 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 accelerati4h;m ;nfvfue:y-2g qion on a horizontal surface for 5.00 s. The block’s kinetic energy umg:2 4hf ;yifq;en-vstrictly 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 )a ar6pfa9-v7mli,2m1bhoov 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 horizpham9 mi)ra- o,fol 62a1b7 vvontal 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 b agx+ta0d6cpdkt4 jtq r0 vyk:6+ *v7nlock for 5.0 s. The block was initially at rest and slides ona: +0k rtg6ddp74tx y0 qan6v*cktjv+ 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 py3 gq40-d y1yraweou; ond throws a 1 kg hammer in one dir;0-yeqwryudy 3g4o 1aection. After the throw, the hammer moves off in one direction while the student moves off in the other direction. Which of the following correctly describes the above situation?

  03.14: A fan blows the air and gives it kineticubpb+2ot.un;/ycu7b bw6g2 m : p-wew energy. An hour after the fan has 72 ww;cub/+ epu6yutp2-.bgmw:n bbobeen 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 3cwmy q0dd:3) po4+p4ov6 z yi x-of/zl.0 m, a speed of 4.0 m/s, an foc6-x/ p y3oy dz4+lq o)dw4vz0mpi:d an acceleration of $1.0\; m/s^{2}$ . What is the kinetic energy (in Joules) at this instant?

  05.05: A box of old textbook 1+l5gud xadg9un *bn/s is on the middle shelf in the bookroom 1.3 m from the floor. If the janitor relocates the box to the shelf that is 2.6 m from the floor, how much da+/u u9dg*x15bn gnl 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 hobfng*k2pq-:qs j3c: f rsepower) 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 car?3 ::-n*g jfqsbpqfkc2

  09.13: In the figure to the right, a box moves with speed 5.00 m/s at thhxkmtmi+x,q14p+ y .jst)ms+e 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 ofF = 240N. The box, of mass m= 20.0 kg, has a speed of 2.50 m/swhenmx1+4+s+k p)itx,yq mmts jh. 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 5.00 m/spdgw59 i)s -hw 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 = 240N. The box, of mass m= 20.0 kg, has a speed of 2.50 m/swhen it reaches the top of the inclpwgws -9id)5 hine.
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,7xjwij ;aep lxsc8ww; 685v3q along a straight road. CarA has tw7;5 p 3v8xaj lexwwwsqci ;86jice 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 speed in terms of B?

  12.07: What is the net force acting on the object durw.; 5 pxkgbwh*7vmb4zing the time interval of the hzxk*v; 5 pg m7.bw4bwacceleration?

  12.08: Through what distance does the object move during the time interval ov g79v roe8 fzo z0ro-:k+2jxof the a0zrz8x+v2 -fg7ro ejooko: v 9cceleration

  12.19: The magnitude of f qg-z1m;k47mdnx xv4as l4r( the linear momentum of a 4.00 kg point mass is changed from 6.00kg.m/s to 14.0kg.m/s in a time interval of 6.00 s. What is the change in the kinetic energy of the mass during tha7 gn4xv;qmd 44r mxs1 -f(zklis time interval?

  14.11: A crate gains 36.0 J of kinetic enerm6f mn2q3*h(j qgzwzo4a(l 1cgy while its speed is increased from 2.00m/s to 4.00m/s. Which one of the following choices best representgqn qj(w4zla(3 fom21chm* z6 s the mass of the crate

  94.38: A force F at an angle fm;ch ssso7id3t(8 wpuyxy*l) 58e g; θ above the 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 fsy;;7h)o5*(l8 xiswgt dfpc smeu8y3 loor and the suitcase is μ. The work done by the frictional force is:

  14.31: A toy crane exn m ;k/xrpb+;xerts an upward force and delivers a useful power output of 0.10 w to raise a block vertically at a constant speed. At m+pk/;nbxr ;x what constant speed will this crane raise a 0.20 kg block?

  12.18: A 1.00 kg object is released from rest nxw gwt8o2kok*0myj4j w4i */x,4r ct near the surface of the Earth, the gravitational force acting on the 1.00 kg object by the Earth does 10.0 J of n4* ,4wijgj wc rko4/kt tyox8*2m0wxwork 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 motionless a height ho above a har+p jd5atvq5l5 d 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 t+v 55 adtqp5jlhe 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 t yluv4j7uo 4xn)hl: a0he car takes 95 ) 7uo:l u4jnxla4v0 hymeters 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 uniformly until it stops. srx3t q4vn+c/ If the ball travels 15 meters, what was the average net force applied while it was coming to a stop? 3/4csvxtn +qr

  02.26: Consider two laboratory carts of different masses but identical kinetic e4 x fp8a4r-ndg2gpsgt3t*j -y nergies and the three folloggt- gd4-2s an x843ypf pr*jtwing statements. Which of the above 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 se;l5 px l7+zanss *8yof clay is tossed vertically in the air with an initial speed of 4.60 m/s. Ignoring air resistance, what is the change in its potential energy when it reacheypl*75n 8l+ezax; ss ss its highest point?

  06.20: A boy jumps from rest straight upward from a flat, st5b -3y:gdeq/eur 6krxq b en,0ationary 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 motion6xq5,/ 3y bgbrr q:nuek0d ee-. 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. Theb3.u,rmj yog5.f(eqd tb 42th object.d54jtf ybqmgu.h ro,e(t2b 3 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 exerted by the ground on the object while coming to rest?

  12.48: An object of mass M is dropped from ahep;l *o-:t . sigxg+4bsdoc r)pdwb9r,ight H above the ground. The object bounces off of a horizontal surface in gc pgotd 9lbxrssr*+ b-)4;iow.d p,: 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 pulled sidp,j236fwspzmd 6kxyx66, :/ dqnhgogeways until the cord makes an an6y2pd,o6 sq6mg/wx, zh n:p 6gd3fkj xgle
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 blgfc0;j1 2s bup a uniform 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 stfjl02bsg ;1cbarting 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 mogxh e(ia,l1 ohqs x8:*ves 10 cartons from the sidewalk, along a 10-meter ramp to a loading dock, wx,sha l e(xig1:qh*o 8hich 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 for 2-wmtr j61edhce F=50N (as shown in the figure) is applied for the 6.0 meter motion of the box upward along the incline. The hr t1d2e-wjm6 mass of the block is M=15 kg. Which one of the following choices best represents the work done by the force F onthe box for the motion?

  04.48: Two identical bowling balls A and B are each dropped from rest frohh.c/ gvu0vb5 i1o1omm 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.vouc ho01/ibvmh g 15 the ground, how are the mechanical energies of the two balls changing?

  11.28: A person throws an object of mass M straight u 3k-6vze /.xdppmefg rpo(c32 pward 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 of mass 0.5M straight upward with initial speed 2v. g 3r3e2oep-6k f/(cdxmpv. zp 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 hax;u+(o/)zr0 wmf:b u qa ep.yos a spring constant of 20 N/m. The potentir/+ e:o(bxoyuz.;mw u ) qpf0aal energy stored in the spring is:

  97.10: A compressed spring has 16 J of potential energy. Wh.c1mj59(gx90gsinu gi3z :l lmmju 8qat is the maximum speed it can impar(jnxm5ulmg 9.ig9 3s 0zqgi8m:j l1cut to a 2.0-kg object ?

  

  10.31: An object of mass M starts from rest at the wl0v*.st toper-3 8f+8zdj sw7(k aqdbottom 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 s30e+7kptw8z-8 o s.qva (rl dfw*tjdthe 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.