Which of Newton's laws besotaky 4fh*dj - ,qvm6 +h/k:fot explains why motorists should buckle-up?

  When you sit on a chair, the resultant force on you3:6ufk kek ckctl cm ++ax4u9; is

  In the absence of an external)+t kixh+3o u)7fcm al force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN y8 1xw5 citho2are suddenly turned off, while traveling in empty spac x2o 5h1twiy8ce, the starship will

  A rocket moves through empty space 8ite+u)cf6vf9 5 s k;zkqk; auin a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the rocket in order qkf ;t98fi usz+ kv)u;ke65cato sustain its motion is

  You are standing in a moving5axepj9c 2 0r+r(dtrn bus, facing forward, and you suddenly fall forward. You cre+ a dp59rcn0txj (2ran imply from this that the bus's

  You are standing in a movininqt 3p8)l 066 av5exg *zco;bxmsbf0g bus, facing forward, and you suddenly fall forward as the bp6o60l veq03xxmf bs) 8b*ig;z anc5 tus comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the object.bh0 :mnz0flt6

  The acceleration of an object is inversely prop d56t/zfic* /4y6legdgne(.e wa: uuoortional to

  A net force F accelerates a mass m with an acceleration a. If wsbs0 7ji -h.nnz9 ro)the same net force is applied to mass 2m, tn-h 97)0b zowsnrsi. jhen the acceleration will be

  A net force F acts on a l9 amzv4 hmb84g3 j*i9saq-tlu5g+c pmass m and produces an acceleration a. What acceleration resulttqp9c-4g vha +mmiz* 3j8b5ulsl94ag s if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloow80rd q o,i(xrn will fly away. This is an illustration8d 0r iworq(,x of

  Two cars collide head-on. At every moment du vx0ijjkcc b,0(pi82q ring the collision, the magnitude of the force the first car exiv0i2c8c kj p0(qbj,x erts on the second is exactly equal to the magnitude of the force the second car exerts on the first. This is an example of

  If you exert a force F on an 0:ykll:wxy 95i+k +)o qy mzj:h0mlizobject, the force which the object exerts on you wio kz:kxl m0iy::yw+) i+hllq0jz m 95yll

  Action-reaction forc-c ia1d0zxghzm.84ioc. ih:e,fykl7 es

  Action-reaction force)/ zkhz38q qads are

  A 20-ton truck collides with a 1500-lb car and 1h2kjy 4u2 wgdcauses a lot of damage to the car. Since a lot of damage is done on the ca42 y 2kuw1gjdhr

  An object of mass m sits on a flat table. The Earth pulls on this object mzo(1;eikgx ho-0dertxq + ;d .it-k0with force mg, which we will call the action f dkh xeo-0t.m;rq ;+zto1eg 0d(-ixkiorce. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The.kzgb b9 fs +6c+ik4ao Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reactioo.z4bs kkf96cb+ ag +in force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous foxye g:73:p k8(x :p 3jaoy:ik oqkzhb6rce. The ball hits the bat with anojoe( yq: 67k:3xkb8pi 3:g:kaxyp hz instantaneous force, whose magnitude is

State Newton's three laws+w ;v cvn+u.ak1.viv1 jwy 4nc.

  Mass and weight

  The acceleration due to gravity is ce9 - yq:q;kfhdj9t,obm 4v7o lower on the Moon than on Earth. Which of the following is tru,ch:yeb9q 4k qo;tj v97fmo-d e about the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force whpbx 2 .r+a uti r3zq.31unszh0ich acts at a distance is

  Who has a greater weight tov ni (q.+ljp3a mass ratio, a person weighing 400 N or a person weighl+. nq(ip 3jvaing 600 N?

  A stone is thrown straight up. At the top of its path, the net foahi*x62snc21exa p+oc l21l p rce acting on in1csp2 xipa h axl +*12c6el2ot is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from thz7k),u 9smgn -w wdbj*e same height. Ignore air resigwbdns7mk)9,*j wuz- stance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal velo g(y ,/1ijp5 gl8y3fb drlo+/o uhqt(mcities. Which object experiences the greater bo/ty+yfir,p(m(8l g/o1 gq5h ud3 ljforce of air friction?

  An object of mass m is ha x38v/vf1 lg(jqbmj+gnging by a string from the ceiling of an elevator. The elevj 1+ fvj(bvlm3 g8/gqxator is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the c xhsa, bc(m--sxarx6, eiling of an elevator. The elevator is moving upwx-mhbsxc 6( xa-as,,rard, but slowing down. What is the tension in the string?

  The force that keeps y;63 abuvmp i 8s/5j bhe7qsou,ou from sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it id uwj9kn mkx2w 1(k//is to keep pushing it with constant velocity (w/dkik jkx1w/2n m9u, because

  A horizontal force accelerates a box from rest across a horizontal surface (fr8qtx01kuhcv(t t4 :,m mx*syx7qm1fjiction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal tt 80sq,xm74jt y1q(k1uc:mvxhmfx* force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at consth6g91(*jw hys 3y9dvivdfx (oant velocity. Thus we can deduce thayjh dvo369(v id9f(yxg h1s*wt

  A block of mass M slides down a frictionless plane inclined at an angle q with 7 jgx6u /kck l1(dd)zgthe horizontal. The normal reactiodgz(xuk7gcdj )k61 l/n force exerted by the plane on the block is

  A block of mass M slides down a friclih/kyi,;- lotionless plane inclined at an angle q with the horizontal- ik,yhl/lo i;. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless /+hs,xlm.fwmplane inclined at an angle q with the horizonta,h+s xl /.mwmfl. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on q zlq n197yc-ean inclined plane that makes an angle of 30e with tq9 7enq y1l-czhe horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 1ludfc i p9+knht rd 5g8-h3i)/6-N force is applied to the object,gt hdc nfh)r/lu+ikdp95-8i3 and it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 k9 homw2v kn .ag7* dw40cc4upig can accelerate from rest to 27 m/s in 7.0 s. What is the a.*9wgoacwiu4m4d 07h2cv pk nverage forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. z0c3b+3p:. y v 5q7skgdftpav What is the net force acting on the bo+qp3f v5kvyda .bg 73tp0scz:dy?

  An antitank weapon fires a 3.00-kg rocket wsvfb je2cg:- 9hich acquires a speed of 50.0 m/s after s9j cfv:2bg -etraveling
90.0 cm down a launching tube. Assuming the rocket was accelerated uniformly, what is the average force acted on it?

  If you push a 4.0-kg mass with the dr6rwf0hjsf3 op-sr7 v3 k)q2same force that you push a 10-kg mass from resp vsrro) 0q-jhf3k7w3fd s2r 6t,

  What is the mass of a 4tmom)s:d4 p hei5mo+sm 4 v9eperson who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of sseczsec* /3ryfa;/)the Earth where th3c/y se*c )r/es;a fsze acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg vj01-q vtw86zep *r w.ncjmc*.:r tbx on the Earth. What is the mass of the object on the sm.xtvcepr0r.1v z*w wnbj qt- c8j *:6urface of the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N o,.i eh-k ti d29otg/zmn Earth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Comp otk gmh-,zt2/i9.eidare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulx5fyg7- : ovq/7-4mlyc xxvyl ling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward Sue ayy -cly7xo7qf4vxxg5:- /lmvt $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless su-0 )s 3slp6r4x(pn eawimq:i c0z8vtzrface. A force F acts on the stack, and it accelera :4zpa3) -q08mxcs ip zline6rts0(wvtes at $3.0 \; m/s^2$. A 1.0 kg book is then added to the stack. The same force is applied, and now the stack accelerates at $2.0 \; m/s^2$. What was the mass of the original stack?

  A person of weight 480 N stands on a s6iqr mx xv3t-2cale in an elevator. What will the scale be reading when the elevator is accelerating r2-v x3ti 6mxqdownward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevato*wx.ynkdp 8kr yfe3( 8r. If the mass of the person is 60.0 kg and the elevat*px(wf88 drekn3yy. kor accelerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an eb(h;v)0)(jy oe ffj2es jc2izlevator. If the mass of the person is 60.0 kg and the elevator accelerates upward with an accele2sfjc(ji0z;j(e e)f)yv 2hob ration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. One force has a magnitude tr.c8ev52bz b v(f3m07 szttpof 8.0 N and is directed due north. The b ztttezvp7cvm(b2805f.3rs second force toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbn47y6fs 7ml )ud*b 7l ct2uu4k;tvbz red of a truck. It is held in place by metal brackets that can exer)z6c tkbl fn 4bl4rm7* 7;v uut27sudyt a maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, what is the minimum stopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg restsemo8rh 8 0nlw8 2h0iugdddc21 on the flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When th o8 lm0c8grh1u2dnid0ed 8 2whe truck is traveling 15 m/s, what is the minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shown inon+hcu8o -y+g Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and th+nug8y+o -hc oe mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M gl5-(k k9 t8y5.5 lufzxure bc ik4xa/= 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pul5l xltua be-4 9r iuk.g5kxy5(kfc 8z/ley.)

  A student pulls a box oftp46qsf4eg t jx3v0e,za 06bc books on a smooth horizontal floor with a force of 100 N in a directioc z4p,x6b6t0 etevq 3gjf4a0sn of $37^{\circ}$ above the horizontal. If the mass of the box and the books is 40.0 kg, what is the acceleration of the box?

  A student pulls a box of books on a smoothn6hw+wns2;)j bu; b, hq0mcrq horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40.0 kg, what is the normal force on thsh2r;uhw0qbn, jw cn+ )6m bq;e box?

  A traffic light of weigh idcug98yhn 79zfl-8 pt 100 N is supported by two ropes as shown in Fig. 4-2. What arep 8gz l7fu9n8-9yhc id the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes armkzz eunj: sb* 0l)pq/y 51mj6e 50 N, what is the mass of the traffic lightzqym *b65 :u)n1jj0pem/s klz?

  Two boxes of masses m jg f7xo:0 bfqya2b9* aand 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more ma ojq9b2g0baff: 7x y*assive box?

  Two boxes of masses m and 2m are in contact with eachu4 z3hy:lo:, ;a hmyja other on a frictionless surface. (See Fig. 4-3.) What is the net force on the mja alh 3yyu;o 4h,m::zore massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4cy q gvk,h4y(l/f( xe2-4.) If the forward force on the more massive box is F, what is the tension in the lvf4 y,y2xcqe/hkg( ( connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) Iv j+wso8za 6q,f the forward force on the more massive box i8+a qo, zsj6vws F, what is the acceleration of the less massive box?

Two boxes are connected by a vj5lap d(; 7cpcord running over a pulley as shown in Fig. 4-5. Bovjda5( ;pl p7cx I of mass
8.0 kg rest on the top of the table; the coefficient of kinetic friction between box I and the table is 0.10. Box II has a mass of 15.0 kg.
(a) Draw the free-body diagrams for the two boxes, identifying all of the forces acting on each of the masses.
(b) Calculate the acceleration of the system.
(c) Calculate the tension in the cord.

  The coefficient of static and 9i2iu f:+8mc3t x 1plmcln, kakinetic frictions between a 3.0-kg box and a desk are 0.40l 8 +n c lmkt21am:fi,cxu39pi and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plas8ygow.,c(io sk p x2p8j2bx(j4 h pi9vtic on wood are 0.50 anji 4ybs8( 8pg22 powv,hkx ix(.9ojc pd 0.40,
respectively. How much horizontal force would you need to apply to a 3.0 N plastic calculator to start it moving from rest?

  An object slides on a level surfbi) zt+uw0fic+q 1l7ikg6i*8do m5 ciace in the +x direction. It slows and comes to a stop with a constant acceleration of b udm8i7f i +k1tqol) 60cgcii*w+iz5 -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surface is pulled by a 5.0-N forcepp--gu/-pkxs3 sisj m6 q5f)f. A 3.0-N friction force retards the motion. What is the acceleration of the s s jqmfu)p--- fipxk36/ gsp5object?

  A horizontal force of 5.0 N accelerates a 4.0-kg masl1m4*5yc ljtjs, from rest, at a rate of $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, a puck is given an initial speeolvp ip +4;y(od of 10 m/s. It slides 50 m on the ice before it stops. What is the coeffp o4vy;(pl i+oicient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks 9a024vrurq ud )0q q-qk0.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing -v dr r4aq 2qu)0q0kuqconditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3)+6ge sp+p2 krz ;;easz2ei pjm are stacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less massive box does notpk j)r 2z+ pp s;a6;gsieze+e2 slide on the more massive box, what is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) Tjl6faq4h3t; d ktpni10w l* :ehe surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rd elh6w43al0f ;:j*1ittnp qkough. If the less massive box does not slide on the more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The pla/*xd/. iakxx ine is inclined at an angle ofdx xi.x/a/k*i $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle3g 40 ee b1) ssbzoj83ojq+ /l7bdsknjmhm(0 u of $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smwl ( e2uby4dr(ooth inclined plane with an angle of $37^{\circ}$ to the horizontal. If the inclined plane is 5.0-m long, how long does it take for the mass to reach the bottom of the inclined plane after it is released from rest?

A block lies on a smooth inclined plt8 72p 5nfc kmo2-mrdbane tilted at an angle of $35^{\circ}$ to the horizontal.
(a) Draw the free-body diagram for the block.
(b) Determine the block's acceleration as it slides down the inclined plane.
(c) If the block started from rest 8.5 m up the incline from its base, determine the block's speed when it reaches the bottom of the incline.
(d) How long did it take the block to reach the bottom of the inclined plane?

  A wooden block slides directly down an inclined plane, at a constant velocit)yu5; r;tykkhy of 5)hk;;rtuyyk 6.0 m/s.
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a mass mxecq3 tql-shv h13y45 slides down a rough $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m8j/ty7sp+qje-ux 9 z b slides down a rough $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. If the plane is 10 m long and the mass starts from rest, what will be its speed at the bottom of the plane?

  A bulldozer drags a log weighing 500 N along a rough surface. The cable attach .32, uymtmreo*)yj ai(zrv2ked to the log ma eoy j2mvr, tm ).ra2(yu*ik3zkes an angle of $30.0^{\circ}$ with the ground. The coefficient of static friction between the log and the ground is 0.500. What minimum tension is required in the cable in order for the log to begin to move?

A 25.0-kg box is released from rest on a rough inclined plane tilted at an an 9kses i+1+vph*d*u uegle ofks+u9i1edepv hus**+ $33.5^{\circ}$ to the horizontal. The coefficient of kinetic friction between the box and the inclined plane is 0.200.
(a) Draw the free-body diagram for the box.
(b) Determine the force of kinetic friction acting on the box.
(c) Determine the acceleration of the box as it slides down the inclined plane.

  An object is placed on an inclined plane. The angle o0aia1b:ax gegh n:3;k f incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the pln:1hk3bg e0 :gia;xaaane?