97.01: A force F directed at an angle of θ above the horizon4wq qdzuix :)7 ec/ou,tal is used to pull a cra) /oiuq7,:zxce q4wud te a distance D across a level floor. The work done by the force F is

  97.33: A softball player catches a ball agvt t,ei* ,8aof mass m, which is moving toward her with horizontal speed v. While bringing the ball to rest, her hand moves back a distanced. Assuming constant deceg*8 t,a,iavt eleration, the horizontal force exerted on the ball by her hand is

  99.14: A construction laborer holds a 20 kilogqoo re- i*mcb4g; ll,pp8w/8 wram sheet of wallboard 3 meter above the floor for 4 seconds. During these 4 secondshow much power was expend,- prg 4wi ;m8* leo/wqc8lobped on the wallboard?

  17.11: A 5.00 kg block slides with unif0 zmmcjo f-a4i z7 +*vomso24dorm acceleration on a horizontal surface for 5.00 s. The block’s kinetic energy strictly decreases from 50.0 J to 20.0 J in t*asm+z mm czoojdf04iv42o-7 his time.
What is the average speed of the block during the motion described?

  17.12: A 5.00 kg block slides with uniform ac)i7 fdrn)wb 0 6y 4zvf 3(jrl(hzxk5rqceleration on a horizontal surffdr6rxl(75 yzqri0n )v( h fjb4 w3kz)ace for 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 block lxan ray yl(;n gpt53m11t24jfc ud4: for 5.0 s. The block was initially at rest and slides on a horizoy31a 2r fyj 1m5(pltgc 4dt:nluxan;4 ntal 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 exea ax*uv qy 043*yclu5j,nrf+qa- e xyfoi)04trted on a 3.0 kg block for 5.0 s. The block was initially at rest and yuf0-ql0ir *af4n,v)yax+oa* c jy3e xtq54uslides 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 frictionlesso;4p hg2w4h fm,j uk*a frozen pond throws a 1 kg hammer in one direction. After the throw, the hammer moves off in one direction while the studenhh4o ; gwm4pkja,2*fut 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 kinetic energy. An hour after the ffpz04 uddnm;psqc .rt;y,)u9an has bem;zu9ctrd)ds,.q ;n4pf y pu0 en turned off,
what has happened to the kinetic energy of the air?

  09.05: At an instant, a bloc8n rur1a/u o4 emsdk a o9k4iveh0)h;-tp 49ask of mass 0.50 kg has a position of 3.0 m, a speed of 4.0 m/s,trk/ 4pnuae-8ah1sor9am 9di04e) k s;o4hv u 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 froym3bxbo k)zt;r j/j./ m the floor. If the janitor relocates the box to the shelf that is 2.6 m from the floor, how much work doejrzkx/b/).ym bj to;3s he do on the box. The box has a mass of 10.0 kg.

  02.32: An automobile 7se xrwpxep)l2;: b3ib a91xkengine delivers 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 max7 psb93x;1akprleb 2ew)i: x gnitude 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 afi n hwrx):/-o+-c xfbottom of a rough, fixed inclined plane. The box slides with constant acceleration to the top-/-haiwcf )xr:+oxfn 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 5.00 m/s 0c 70ss1flw h8huvjuyd +1u*,z(9mbkd ftg;iat 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 00mhs 9hzc8b7 s+j kg*lfu(wv;1,dd1yt fiu uthe 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,go7 sh)xkljd9 qg+g 4nn5rc8bzm,- l7 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 trav74k 95+g7zll njd,-rx gn m)ogbcs qh8eled 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 time um6r6/xu b+c *h( vkm3edq2dlinterval of the acde h lx+u(m6qc rumdv2k/b63* celeration?

  12.08: Through what distance does the object move during the timexr,:bvp(pv ;ma j1qm : ;7xsqd interval of the (sma q:, 1xd xp;v 7qmrj;pv:bacceleration

  12.19: The magnitude of the linear mo;kfd2 u0 2cmfomentum 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 tf2d ; ck2uo0mfhis time interval?

  14.11: A crate gainsdjy.(;a)y kja5pf2o7z4ossa 36.0 J of kinetic energy while its speed is increased from 2.00m/s to 4.00m/s. pofa2 s.7 j k;(jao4azdysy)5 Which one of the following choices best represents the mass of the crate

  94.38: A force F at an angle θ above the horizon9+ojsf3r.4 bh/:m0 qdbs ihxgtal is used to pull a heavy suitcase of weight mga distance d along a level floor at constant velocity. The coeffiojfrgxsmbihh s: d0 q3+9 b4./cient 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 delivers a uswf.+:zyrd. baeful power output of 0.10 w to raise a block ve:+.rd ybwzfa .rtically 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 released from rest near the surface of the Earth, th yqx40evq 0n52u8 wpcje 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 bvu05 8eq2pwcy jx4 n0qest 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 hard floor and rele z7d jxz+zpf fd,aswl1;o+vyk4, r9k -ased. Assuming that the collision with the floor is elastic, which one of the following graphs best +jl-vx ;y4+pzosdakff9k,w1 7d ,rz z shows the relationship between 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 sees a be;f4exi 4/kkeeif) (:f)ske- r,md ga arrier ahead. If the car takes 95 meters to come to rest, what is the magnitu(frked-eik4fk i/e ge:s4m)fxe ; a),de of the minimum average net force necessary to stop?

  00.26: A 500-gram ball moving atr ,6ajiod2vbtaj v1 q20i4s,c 15 m/s slows down uniformly until it stops. If ,i d20rb,jo4 ta12q6sv cvaijthe ball travels 15 meters, what was the average net force applied while it was coming to a stop?

  02.26: Consider two laboratory carts of different 8 2 ;c ytzfv*bldqq7z1masses but identical kinetic energies and the three following statements. yf7qbq 2c1* dv8t; zlz 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 of clay is tossed vertically in the air with an ) f x-tzm(dnh14o;is 5 yjl)orinitial speed of 4.60 m/s. Ignoring air resistance, whayniljz1(-5 ;mf)4)os rod htxt is the change in its potential energy when it reaches its highest point?

  06.20: A boy jumps from rest stiev lok5hh o1e)5,9o7meeq +eraight upward from a flat, stationary concrete surface. Th51emheoo5e 9lie,7 +o qvkh)ee 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 the concrete do on the boy?

  02.48: An object of mass M is dropped frombzx a9pdt+- t/ c:7:ot yjtbu- aheightH above the ground. The object crashes into some soft earth and comes to rest b:c /bjuz-atd7 yx: 9-otb+ttpy 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 M2t rmz(sd 4y1cbggt22 is dropped from aheight H above the ground. The object 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 fog2 2 2 bmdyscz41trg(trce acting on the mass during the collision with the surface?

  96.38: A pendulum bob mass mon p,df t).s:j ;ot(pgyfa cord length L is pulled sideways until the cord mj; ts.fpo, d yt(:pfg)akes 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 u9)bzc6 xy,lp3xz5d j qp a uniform incline of unknown angle. The sled, which started9yjp zx)6 z35qcl ,bxd 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 the sled's speed when it returns to its original position at the bottom of the hill?

  06.09: A deliveryman moves 10 /ze u o6234 cpwqcedqa3ys,1ncartons 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 delivec w/6pqez3ao12 3es4cynq u ,dryman on the cartons to move them to the loading dock?

  12.16: A constant force F=50N (as shomsrr) lt 6f3zi.xj-5l jl-fk hafk2,3wn 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 f3 sh2jrfl zk5k-lflr.x3)m, aj 6-itonthe box for the motion?

  04.48: Two identical bowling balso- d- 9*woily-f6 fmels A and B are each dropped from rest from the top of a tall tower. Ball A i fwd9- -fie6-lsom*oy s 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 objeu5g3 i 2lyr7fgb. xslo8 y 0zth 93rjay:wj3(zct of mass M 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 0.5M rise above the launch point? Ign5 us (i373yr0h 8:tyyazjr g2 f.wxb ojlz3lg9ore air resistance.

  96.20: A force of 10 N stretches a sp dg(4)nvj.d9c yshd*e ring that has a spring constant of 20 N/m. Thecn*d9j(.vsy g)e h4dd potential energy stored in the spring is:

  97.10: A compressed spring has 16 J of potential energy. What is the maximu pwnxs5.,z94nrgx /olh:t) x ym speed it can impay .h:xnp,9wg z4lro/nt5)sx x rt to a 2.0-kg object ?

  

  10.31: An object of mass M starts from rest at the bottog(6zljwc+* 5s ys :yq2+jcbz vm 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. Hosbywgjv*q c2l sz:zj(y5 c++6w 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.