97.01: A force F directed at an angle of θ above the horizontal is used )d nnm97n95pslmq) :p)h iu,f v9gr0 jv8n fnuto pull a crate a distance D across a levesjp)q p g99ih vrlfv5uf:m7n, u9 d)n0nmn 8n)l floor. The work done by the force F is

  97.33: A softball player catches a ball of mass m, which wuv kgn 7y w 80,,lk7-sbqtsh4ktt5 :(yd 9hrlis moving toward her with horizontal speed v. While bringing the ball to rest, her hand moves back a distanced. 0,g sk8ywwl ,:sk(tvdhyt b7l59rnuh-7tk q4 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 wallbogg83n.s fx( b/.ud efvard 3 meter above the floor for 4 seconds. 8/vx.nedg3 f.fg(sb u During these 4 secondshow much power was expended on the wallboard?

  17.11: A 5.00 kg block slides with uniform acceleravvki e94g7:lhtvswhx6q: *c1 tion on a horizontal surface for 5.00 s. The block’s kinetic energy strictly decreases from 50.0 J to 20.0 J *ic xkv67v9es q4hht1w:g:vlin this time.
What is the average speed of the block during the motion described?

  17.12: A 5.00 kg block slides:ukc meg+5) m -btmrk:c-wd)x with uniform acceleration on a horizontal surface for 5.00 s. The block’s kinetic energy strictly decreases fromwcdm-5cm-ure:k + g:)mk)btx 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 blockb9wfvpinskqtt9h9- o 4)g, 3t for 5.0 s. The block was initially at restsgwt9o tbvf -n4p t99qh3ki), 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 forc. )ib :xwkn /e8z 05coaxqutx,e directed to the right is exerted on a 3.0 kg block for 5.0 s. The block was initia.az k n) /bxiceq xut5,x0:ow8lly at rest and 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 thrqbu4 wo :e1th7ows 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 following correctly describes the above situ7bq14oh ut:we ation?

  03.14: A fan blows the air and) xzcule +6a/v gives it kinetic energy. An hour after the fan has x+)cev/ 6 aulzbeen 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 )kmtq:n)zw. t4 7yl tr3.0 m, a speed of 4.0 m/s, and an acceleratirt7mz ) w: )k.n4qltyton 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 ed3t-f,q koot) j(nyq1+q hc0 co2v.x m from the floor. If the janitor relocates the box t+ho.ft -kcxq)eq2y(od jv 3n 1t,cqo0o 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;h9dwe9evw- l watts (about 32 horsepower) of power to a car' ee-lw9;w9dv hs 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?

  09.13: In the figure to the right, a box moves with s me3)v vmym52dpeed 5.00 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 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.mv)5 mdv ye3m2
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 speed8liphb j r,3a( 5.00 m/s at the bottom of a rough, fixed inclined plane. The box slides with constant accelera(ap jl 83i,brhtion 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 tvc-hx p5c:c1g /yc. yzzo9 -iy:oigp4o the right, each starting 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, wy-copv 9g-.yg1ph c/:xcc5:oiz4zy i hat is its speed in terms of B?

  12.07: What is the net force acting on the object during theu2 i)1a,r5hp aht;p)j,ge dte time interval of the accelerati52 ;r),pt a1,u)eedhgj thiapon?

  12.08: Through what distance does the object move during hxaird;k/ 0v .pqu;i9 fgia08the time interval of thv a8if9 qrd.a/ x;0ikh0 pgu;ie acceleration

  12.19: The magnitude of the linear momentum of a 4.00wlvgm8v)mo fnj7/nv) o(z6er2 xtc4- kg point mass is changed from 6.00kg.m/s to 14.0kg.m/s in a time -z6rvnj v))gx 2 owelfco4(m v/87tnminterval 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 e*p5 n*dwkpar 6jr5w5 znergy while its speed is increased from 2.00m/s to 4.00m/s. Which one of thk wj5 5nwa*p* zprdr56e following choices best represents the mass of the crate

  94.38: A force F at an ang9fq fsurtv s*) -h o.tk;w:/pvle 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) h o:;pttk fs9q./s-*fvwvu r floor and the suitcase is μ. The work done by the frictional force is:

  14.31: A toy crane exerts an upward force and deliver km;u,gbgsilj n(e;r als06x)jq9/ w0s a useful power output of 0.10 w to raise a block vertically at a constant speed. At what constant speed will this crane r lag kx(ms9)00r wgs;/;i6ljjeubq , naise a 0.20 kg block?

  12.18: A 1.00 kg object is released from rest near k)r0.ag+ kpz jqj;ku4the 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 ojr kj. zk ;0gqkuap)4+ne 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 heigan4)f fvu;m b28dn 2(qj6eufjht 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 u2)en;8vd fj 2nm6(bju4qa ff the total energy E of the ball and its height h above the surface?

  07.06: A 500-kg car is moving at 28 m/s. The driver see pjp-kgqi72(ay;c.iz s a barrier ahead. If the car takes 95 meters to come to rest, what is the ; (izp7qk.2gpyi ca-jmagnitude of the minimum average net force necessary to stop?

  00.26: A 500-gram ball moving at 15 m/s slowap u230n d7lmcjft ewum03; g3s down uniformly until it stops. If the ball travels 15 meters, what was the average net force applied while it was coming to npeu mj ;m3ft0uaw2 dg303lc7a stop?

  02.26: Consider two laboratory carts of different masses but 5 lhg*ym7l xy*identical kinetic energies and the three following statements. Which of the above statements would be correl5*y y*gx m7lhct?
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 fa:km0 b lv2gw21q8 cethe air with an initial speed of 4.60 m/s. Ignoring air rebfwmla120q2ve gck 8:sistance, what is the change in its potential energy when it reaches its highest point?

  06.20: A boy jumps from rest stfzbxac0yv;g +c. 1q(e raight upward from 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(yg zq av;x0efb.c1c + 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 aheni.;ug9 rrpm6m8o +js5mbfp- (gh0b nightH 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 exerte.b -n6opp grb8;h9+ ms0munf5r(i m jgd 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.mj - iuuswc.*; dx 7vgp3+jj1b The object bounces off3*-b 71;jms.jdwpi +xcu jugv 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 on the mass during the collision with the surface?

  96.38: A pendulum bob mass mon a cord length L pr.v t1 33hwfkkz(lf l.;fo*pis pulled sideways until the cord owk3r1lp. l ftkhp3*(zvf.; fmakes 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 slides48+vd maqhzs +w om.2o ,gl.vu up 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 starting position and momentarily comes to rest. The sled then slides back down the hill. What is.woz+h8+ lqv d4 avsg.ou,mm2 the sled's speed when it returns to its original position at the bottom of the hill?

  06.09: A deliveryman moves 10 cartons c -/ftv+oxc5 rextxc( vru7-6 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 deliveryman on the cartons to mxc5-t 7rf6(xoccvvut +/-e r xove them to the loading dock?

  12.16: A constant force F=orzj/qztrkt 0c/v un-f/6* t,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,u/r-tt z qvk 0to6j nc/r*zf/ 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 from the t dg7r0f+ysva2k7 20tcbp yc;p op 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 gds brv+0a y2tfc0c7 p7p ky2;the mechanical energies of the two balls changing?

  11.28: A person throws an object of mass txn,/1dfl..uoq.fi p gz3 ,yu6w kc/ ( lttr(fM straight 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 of mass 0.5M straight upward with initial speed 2v. In terms of H, to what maximum height does the object of mass 0./( tffu cqflrg 61iuk,3lwtp./ xt.don( ,y .z5M rise above the launch point? Ignore air resistance.

  96.20: A force of 10 N stretct/v qfq dod(5gtxru m.( )xm63hes a spring that has a spring constant of 20 N/m. The potential energy stored mo m /xdgr35vdu.(t(6qqtx)f in the spring is:

  97.10: A compressed spring has 16 J of potential energy. What is t*aaja cs9ec dlb( 5w:*he maximum speed it can impart to a 2*ls :a5jd9 *wcceaab( .0-kg object ?

  

  10.31: An object of mass M starts from rest at the bottom of a fixk2e *cgiji4dyp s-;as1b g67eed 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 pers;- 1b cydsi6e7eij2*sak4pgg on 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.