97.01: A force F directed 4 fn7da0wln(lzo ky)-at an angle of θ above the horizontal is used to pull a crate a distance D across a level floor. The work done by th-df 4n zy0(olwk7) alne force F is

  97.33: A softball player catches a ball of mass m, which is moving v1jn l3 logj50toward her with horizontal speed v. While bringing the ball to rest, her hand moves back a distanced. Assuming ojlvn0j 51l 3gconstant deceleration, the horizontal force exerted on the ball by her hand is

  99.14: A construction laborern9hcg /znc:g qk2s*+ z holds a 20 kilogram sheet of wallboard 3 meter above the floor for 4 seconds. During these 4 secondz +g2 nnszc9hgq*/ :ckshow much power was expended on the wallboard?

  17.11: A 5.00 kg block slides with uniform accz4zf /b6y) cibeleration on a horizontal surface for 5.00 s. The block’s kinetic energy strictly decreases from 50.0 J to 20.0 J in this timcfi4/y) zzb 6be.
What is the average speed of the block during the motion described?

  17.12: A 5.00 kg block slide/ kyey(ohqq)asa7ms gv(yr - yp hm/1-nq68 ,zs with uniform 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-17s,qy)qnm8/yyka z me r vhh(po ag(s y/-q6his 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.why91 r;f3mrex bo5 1j0 kg block for 5.0 s. Thebhm 1r f91oj; w3yrex5 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 direiglm *;ec) wbb-lw3u4-h3 kwl cted 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 horizontaw)-w3i hb lwl4*3-kl ;ugcebm l surface.
What is the kinetic energy associated with the block after the 5.0 interval?

  00.15: A student initialn6/vz fj 32ajhly at reston 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 directij f3za26vh/ jnon. Which of the following correctly describes the above situation?

  03.14: A fan blows the air and gives it kinetic energy. An7(/kh fbqj:gj hour after the fan has been turn(g :bqhjjf7 /ked off,
what has happened to the kinetic energy of the air?

  09.05: At an instant, a block of mass 0.50 k-sof zvg *g .)ppl9 :zo/6qqkhg has a position of 3.0 m, a speed of 4.0 m/zp)g9kz goh vq.6 poq/-*s f:ls, 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 book0thdk aug(-kj gt5r1 (room 1.3 m from the floor. If the janitor relocates the box to the shelf that is 21 tj5(g0t(rh-dkaugk.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 watts (about 32 horsepower) of poweilhj.5 p8l2z* a0 ryxfr to5xp0 r fl*l2y8h ij.za 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?

  09.13: In the figure to the riglhnomd :1d gr 8,)n;x- x9ard:sit f8nht, a box moves with speed 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 t8 9 nxdfnl)hsr tdndgmixa- 1,;8:: roop 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 at thw*po wp;tzyj85tjr o 21g5d ;je 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 ztd2r55wp opygj o8 ;tj *1j;wthe incline.
How much work is done by the applied force F to the box?

  11.30: Two cars travel to the8tqjxwe vkv9m,x3m0u. k 47sw 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. Whent97j03xke.vw wv 4,8 uskxmm q 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 duk/:4hqpgn j7n bn e**sring the time interval of the aehs* 7q kn/p4ng: j*bncceleration?

  12.08: Through what di3bpmzvzi b -5-stance does the object move during the time interval of th- p3izmz -vbb5e acceleration

  12.19: The magnitude of the linear momentum of a 4.00 kg point 4rx0q2a6m ix,o2dmc-u x5 saqmass is changed from 6.00kg.m/s to 14x 65as4uc x2-xr2a, midmoqq 0.0kg.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 6txp/d.okt0 w,dq oy+while its speed is increased from 2.00m/s to 4.00m/s. Which one of the following choices best represents the mass of the cratw+qd6t ok yxdo, .0/pte

  94.38: A force F at an angle θ above the horizontal is used to pull a heaulra7oo tj;oh(k) gg f/4g -+9yiaeo ,vy suitcase of weight mga distance d along a level floor at constant velocity. The coefficient of friction between the floor and the suitcase is μ. The work done by the frictiona/k+o auoh oi 9()7jagt4geo ;,y grfl-l force is:

  14.31: A toy crane exerts an upward force and delivers a useful power output oftj7mx/ 15ugm6m4kk 57f nxskt 0.10 w to raise a block xm7 6 s7ufg5t k54k1mtjmx/knvertically 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 t3 yeh7byd0 ho*ikb l78h 5fa)from rest near the 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 one of th)ibh 8bk37*a7lo f h 05yydehte 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 yth2) *vidpg 2a hard floor and releasedth2i y)vgd *p2. 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 height h above the surface?

  07.06: A 500-kg car is moving at 28 /,,sbw4vb 9 noph8hfxm/s. The driver sees a barrier ahead. If the car takes 95 meters to come to rest, what is the magnitude of the minimum average net force necessary pf9 xhbo /hwb4,8v,snto stop?

  00.26: A 500-gram ball moving at 15 m/s slows down uniforsz)5/+irjwo3sjt +-3 j gj ;efclcqc4mly until it stops. If the ball travels 15 metersowj3z+i-/4;)sg r j+jlqcsec5tfjc 3, what was the average net force applied while it was coming to a stop?

  02.26: Consider two laboratory carts of different masses but idened-6m 8vr h y5ipi4j0:od8 u j,fa,lpwtical kinetic energies and the three following statements. Which of the above statements would be correct? vjo08jy5 ea,l4dpp 8uw r -fhmi i:d,6
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 ia7w5zty9 fs;y n the air with an initial speed of 4.60 m/s. Ignoring air res; fswa 9tzy7y5istance, what is the change in its potential energy when it reaches its highest point?

  06.20: A boy jumps from res(-h jde7/-j.vefn cx +lek 7rht straight upward from a flat, stationary concrete surface. The cd-vhee e 7-njk. l7jr/fx+ (hboy, 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 b c97xom;xusw;7jd 2asrw9 p5is dropped from aheightH above the ground. The object crashes into some soft woms7r979sj a2wdbp;;xxuc 5 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 froc i9 yq)w8a1ots (pho)+f6 fssm 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 force acting on the mass during oy +ot (6fcaiws )1qf s)shp98the collision with the surface?

  96.38: A pendulum bob mass mon a cord length L is pulled sideways z4wh7/ w,c rlbuntil the cord c/4h7w, bzrwlmakes 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 upc 10dwlbs s1*h a uniform incline of unknown angle. The sled, which started at the bottom of t1cbls1* 0wds hhe 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 cartons fjs,(od0wotztwai te90c* 5yy. 2 we 0jrom 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 2 0d5e w tic0,jyj.2a(ww0o *eyttoz s95 kg, what is the total work done by the deliveryman on the cartons to move them to the loading dock?

  12.16: A constant fokc, :uy0ayh sh5ukx.8rce 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 the following choices best represents the work done by s.hch:xy 0a,u5k uk8ythe force F onthe box for the motion?

  04.48: Two identical bowling balls A a2t+/g(efnjw f vsihmk::a*f3 nd B are each dropped from rest from the top of a tall tower. Ball A is dropped one second before ball B. j:: 3kaef ts *(fn/+himf2gvwAfter 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 an ipi +s 9,zy2 *vqdibok51u4n ngnitial 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? Ignore airi 9d+invyq up*z sb 4n2o1k,g5 resistance.

  96.20: A force of 10 N stretches a spring that has 6fac+4oq (tvspgg./ l a spring constant of 20 N/m. The potential energy st otla.(4 gqcs gp6/fv+ored in the spring is:

  97.10: A compressed spring has 16 J of potential energy .sx ;gj: qpcmqut64/dw ux:y3. What is the maximum speed it can impart to a 2.0.;m xj:twux/4pd3y: qucsq g6 -kg object ?

  

  10.31: An object of mass M starts from rest at the bot, kah e4d32/l68hhf ct y-vdtvtom of a fixed incline of he-h 8lv4y,3kfed a2tdc/h6v ht ight 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 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.