97.01: A force F directed at an angle of θ above the ho2my9ldo f 5e9wrizontal is used to pull a crate a distance D across a level floor. The work done by the forcfwl9 yd5oe92m e F is

  97.33: A softball player catpt u5m8wm u8+uches a ball of 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 deceleration, the horizontal force exertedpm uuu8t+ w58m on the ball by her hand is

  99.14: A construction laborer holds a 20 kilogram sheet of wallboard 3 meter p)ixg7s ii7l 2above the floor for 4 seconds. During thipli7xisg ) 72ese 4 secondshow much power was expended on the wallboard?

  17.11: A 5.00 kg block slides with uniform ac. 1qd;blyp c8cceleration on a horizontal surfac1 y;bcc8dq pl.e for 5.00 s. The block’s kinetic energy 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 accelerata2tt)( yn(. lg6xvqq lion 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 time2y(( 6)ltq.tql xvgan .
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 rightmevm+(v0mq-ke7*h8+qfdr s j is exerted on a 3.0 kg block for 5.0 s. The block was initially at rest and ehkv+d-( j 708ms re*qvmf+qmslides 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 directed to the right is exerted on a 56sfq0v6u( ww-diid t5sop8j 3.0 kg block for 5.0 s. The block was initially at rest and slides on a horizontal surfp-w56qi8 w(d tj5dsiu0o6fs vace.
What is the kinetic energy associated with the block after the 5.0 interval?

  00.15: A student initially* j)n3cvql:7n xhh q93egim; 7 +zfwzm at reston a frictionless frozen pond throws a 1 kg hammer in one direction. Af+ 7qqhze: g x3nc7jl*m39hiwm f )zvn;ter 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 a5z/gxski0xt.w:q2tnl jg* et,v l6 9rir and gives it kinetic energy. An hour after the fan has been turned off,*qgtew txt./6zjg9ixvks5, ll 0:n2r
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 ofk9mewgc/gh3f;+ s 9lm-ex3 yg 3.0 m, a speed of 4m gymwkh;g3 x9e /+9f3 sg-ecl.0 m/s, 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 thjn)m 4vs5, 4kvth;afmolj1 j8e bookroom 1.3 m from the floor. If the janitor relocates t1h;j)k lna 8m ftv,jv54o4s jmhe box to 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 delivx:tfnk iyv-f;0uw/2 .1 mk u2 hxm0jhaers 24,000 watts (about 32 horsepower) of power to a car's driving wheels. If the car maintains a constant speed 2f1 kf:-u.ui02vax kwx mmh;h/ jytn 0of 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 x)jobn w5 ct71with 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 1c57n btxw)o jkg, 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 boxi/wq,fbn) br,i xz t*dlp1 8)pniyi+) 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 ir nyqpln wp*d8fii t )1b)x,bz,+ii) /ncline 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 stpsrnq0n hb:.b/,6 * ajl5q0tjgctg 4tarting 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 tbpg/l rt604,*q05g a.jhnnbj qt :ctshe same distance F, what is its speed in terms of B?

  12.07: What is the net force acting on the object du+sz y 4k0oukhzs) z2r() t-snrynf7 6oring the time interval of the acceler n z))(ko4n-skyry 6tzfsou sh2+rz70ation?

  12.08: Through what distance does the object move duringuzh.d 6fav8 8gy:7bv p the time interval of the acceleratiob:pugvzh8yd.78 a6fvn

  12.19: The magnitude of the linear momentum of a 4.00 kg point mass is - ,tpqom 00x dshv/2zhchanged 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 ene hp-,hmvqz/xost0 0 d2rgy of the mass during this time interval?

  14.11: A crate gains 36.0 J of kinetic enipsmn43hp tp gn )xo*8. lr+9cergy while its speed is increased from 2.00m/s to 4.00m/s. Which one of the fopstlr . m3nxgnip 8 9+4h*)ocpllowing choices best represents the mass of the crate

  94.38: A force F at an angle θ above baefl u94oqc9 sn-,g gc*o)qd*xv1y0 q a; 6tpthe 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 floor and the suitcase is μ. The work done by the frictional force0sn o cg,d l4-ae1bq*cp9xfv * ;gq t)y9qu6ao is:

  14.31: A toy crane exerts an upward force and delivers a useful power outd zn-o96b-chi9qnq 3l put of 0.10 w n hbil3dq6-z o-cqn 99to raise a block vertically 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 r+ r5kfu-lbx6beleased 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, w+ xrk l6fubb5-hich 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 harc jg/- )mm m4gbj6f iut,*k1dod 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 height h abomkfm4-tb md)1i/,*ju c ojg6 gve the surface?

  07.06: A 500-kg car is moving at 28 m/s. The driver sees a barrier ahead. If5t e- 2nq b9r0zlgdf6t the car takes 95 meters net6 9f-r0zd lgb5tq 2to come to rest, what is the magnitude of the minimum average net force necessary to stop?

  00.26: A 500-gram ball mdp(*:er p(e* vxldh-c xd8z(poving at 15 m/s slows down uniformly until it stops. If the ball travels 15 meters, what was the average net force applied while it was c crldp:xpz(pd*e( * 8eh-v(xdoming to a stop?

  02.26: Consider two laboratw-t-l3ub ,qnfory carts of different masses but identical kinetic energies and the three following statements. Which of the abovwn3,- qtbu-f le 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 il:u..y t;5gufenm5d an initial speed of 4.60 m/s. Ignoring air resistancet.d;ei5y.mn l5:uu gf, what is the change in its potential energy when it reaches its highest point?

  06.20: A boy jumps from rest straight upward from a flat, st (m 77/advfciwationary 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 cocfdm7w( iv/7 antact (N) between the boy’ s feet and the concrete do on the boy?

  02.48: An object of mapd/w nd k v.o.nzh667ess M is dropped from aheightH 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 7vpekn o6dh .w. zdn6/force exerted by the ground on the object while coming to rest?

  12.48: An object of mass M is dropped 6 jr 0;b* ; qyg,hs(xrtrmumw (g1cl1rfrom aheight H above the ground. The object bounces off (l1;mjq1yrcxhm0rg rwr*ut; ,s b (6g 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 (w jn7bs wn- zm4tbd ,env+,k-cord length L is pulled sideways until the cord makes an a, n,m kntj7+ -bb dez(-nwv4wsngle
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 unifpn- e dm.9,basorm incline of unknown angle. The sled, which started at the bottom of the inc 9p-b dna.ms,eline 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 from the sidewal*5yi aw,t( gndk, 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 oniygn5a t( *w,d the cartons to move them to the loading dock?

  12.16: A constant force F=50N (as shown in the figure) i8p vjei w95ly(q)bzxn jm+m*8 s applied for the 6.0 meter motion of the box upward along the incline. The mass nm )jw9yqxpv*(8m 8be zi +5ljof 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 from the tsc.cg8mo.fj5 j, pmb,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 are5,cjsb8.opm .mgf,c j the mechanical energies of the two balls changing?

  11.28: A person throws an object of mass M straight udaw4*an*y0kem dq1; 9n:mjb epward 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 stra*qm41 d:0*wdm9 bnj enea;ykaight 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 spring that has a spring co ,x:f.zy;mzk7 9gfa2nqo tmc (nstant of 20 N/m. The potential energq;.m y,tof(k2 f zx9gazc:7m ny stored in the spring is:

  97.10: A compressed spring has 16 J of potential energy. Wh)w*b-tm y 0mo2* icwunat is the maximum speed it can impart to abc o20t m)u-wy*i wmn* 2.0-kg object ?

  

  10.31: An object of mass M starts from rest at the bottz o5448 dytqomn5u sc0om of a fixed incline of height H. A person decides to push the object up the inclq0yo z4o58msu 4 n5tdcine 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.