Which of Newton's laws best explains wah b.zi ufx9m6q) .5kdhy motorists should buckle-up?

  When you sit on a chair, the resultant fog.8 txbh0z;dd l u61ffh fkm;*rce on you is

  In the absence of an external force, audkoemv; - )7 oqm( c/92i4,gauxzfy w moving object will

  When the rocket engines on the starship5)wu +v 2hu: ohgacem7 NO-PAIN-NO-GAIN are suddenly turned off, wcv w5o+u27h m ehg:)uahile traveling in empty space, the starship will

  A rocket moves through empty ss,gce1uttm /)ck;kpc2 *czdy q a2o0: pace in a straight line with constant speed. It is far from the gravitational effect of any star or planet. y;)k,s*zcceo / 1:amtckq cg2pt2 u0d Under these conditions, the force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, ei(c--wvf56(3 mljfr obj ix:and you suddenly fall forward. You can imply from this that the bujo(x5m-fiv:i 3c -r f6(be jlws's

  You are standing in a qetc8qyvj 6 b+e52p u;moving bus, facing forward, and you suddenly fall forward as the bus comes to an immediate scjqu +2;5 86qebeytpvtop. What force caused you to fall forward?

  A constant net force acts on an object. Describe thvxi thre1 y4m;;cz+ z9e motion of the object.

  The acceleration of an object is invervvp v .hu2m-wj-e4l c,sely proportional to

  A net force F accelerates a mass m wipn/bjy6r;se4k;ulo):xqj1 j.g /nxx th an acceleration a. If the same net force is appl6jlx jxg) ;y/j;:p1 nx o/squ4nbek. ried to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What afn)jvq mu7r2cor+ 1r0 cceleration results if a net forcr7)+r 1m2 vr0jfocnuqe 2F acts on mass 4m?

  If you blow up a balloon, and then 2yn 78riox 9hxrelease it, the balloon will fly away. This is an illustration oxn2 r8hi97xoy f

  Two cars collide head-on. At every moment during 8lb gjfmk 7m;.ss 5zd.the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force the second car5 kgz.7.jmblfm;s8 s d exerts on the first. This is an example of

  If you exert a force F on an obj nesc3l1sockxf 6a:k dd04;e 9ect, the force which the object exerts on you will9dk k6ccnoxf:1eas4ld ;s03e

  Action-reaction forces/ oz-fold4gj2sp)/xdo -ge 8*hhcba9

  Action-reaction forc;9vax)xd u5xa es are

  A 20-ton truck collides with a 1500-lb car and causes a lot oxd/9)rs y3uda7u/ e xwf damage to the car. Since a lot of damaxy / /uades9 3)dw7rxuge is done on the car

  An object of mass m sits on a flat tabl,p:b c5cml7zyj6rs, a -pn an-e. The Earth pulls on this object with force mg, which we will canjlcsabnc-p r67p5y,zm: -a,ll the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by u+j-(2m u rqynmeans of a string. The Earth pull(n- uuy2r m+qjs downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N ins- r zmlt0p01.qbknx a.tantaneous force. The ball hits the bat with an instantaneous force, whose magnitub zal0n q. .-kt1xmr0pde is

State Newton's three law a8f)b4x1ldsy s.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Whic4-7vfqan )crm(a*e -q ab+f cnh of the following is true about the mass and weight of an astroc) c rnq+af*a-4e fam- v(q7bnnaut on the Moon's surface, compared to Earth?

  An example of a forceftu1 uv )p+pwmanp682 which acts at a distance is

  Who has a greater weiq);;idnle7--f; (zkboz8z rew thjm7ght to mass ratio, a person weighing 400 N or a person weighing 600 N?f 7m;z 7wbd8z(;k) -ni e;qzothle-r j

  A stone is thrown straight up. At the top of clb/c 8 rd.tj.its path, the net force acting on it ir8 tb/lc.. djcs

  A 20-N weight and a 5.0-N weightdx:i .2ob/ czc are dropped simultaneously from the same height. Ignore air resistance. Compare their aco2b xcz:.d /iccelerations.

  A brick and a feather fall to the earth ai37j-j d:die qx/ ow3aefvuri7g +;s93y:mhwt their respective terminal velocities. Which object experiences theii9 xg jqem+do;3i:73d3f/7u w :yv s-ejwrha greater force of air friction?

  An object of mass m is hanging by a string from the ceili z f*)d:ylvg2kng of an elevator. The elevator is moving up at constant spdlzk g2f):y* veed. What is the tension in the string?

  An object of mass m iszqx/4zfb 2 3)0h)q 9pu icbssv hanging by a string from the ceiling of an elevator. The elevator is moving upwar pbu/x09 q)34sh2 sczivqzb)fd, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on a3s6.j ng b*g (*r1tvai i(nqe5pvmc9zn icy sidewalk is

  It's more difficult to start moving a heavy carto3w 4l+3pyasy in from rest than it is to keep pushini3+sply3 a wy4g it with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (s v9c6 ten:3hyf.lsv (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that thevvysh(3:e9tf6s l nc. horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant veibm -yqbsik1+hp7 l0-locity. Thus we can deducsk1piy07bqmi b - l-h+e that

  A block of mass M slides down a frictionless plane inclined at t3v,tv8 c2ya qan angle q with the horizontal. The normal reaction force ext,8ac t 2qy3vverted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at ahf:p)l2*e2byly g l4 an angle q with the horizontal. The normal reaction force exerted by the plane on the block isb 22gealy:) lhp4*yfl directed

  A block of mass M slides down a frictionless plane inclineqxlk- nbm3 knj(k*i 9cm h9**zd at an angle q with the ho*-ihqm*kzc9mk9 n3 jbn* kl(xrizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kghi km, f8n,.pz) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being rel, ki.hnpf8,zmeased.

  An object sits on a frictionless surface. A 16-N force is ap 9vmaqc 0 k;ifdbcc:70(kyrq 5plied to the object, a0 k crq0v qm;fk59a7 cb:dyci(nd it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can acceleratenhfrzq72hi /m ,5:jda from rest to 27 m/s in 7.0 s. What is the average ,zrj ndhmaq7/f i25:hforward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed o xxjvsq qiq039 /l-qro25 c6spf 8.0 m/s in 2.0 s. What is ths sqr29q6o3ivxqp0c qj/-5lxe net force acting on the body?

  An antitank weapon fires8zik8/fa 9 kch7xsvz0 a 3.00-kg rocket which acquires a speed of 50.0 m/s after trave / akk0zf9si7hvcxz88ling
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 same force that you push a 10-kg mat3dl4 gms3 g-sss from rest, -sdlg3 43sgmt

  What is the mass of a person pk md/ gp,dxq 5wu( ia0/edp8.who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Earth wheotz3mih (x)jobu i6- -re the acceleration due to grt i(hj-ibo3-mzo)ux 6avity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the object on*io.vh)llez d7h(xl3 the surface of the Moon where the acceleration due to gravity lvh*)zx .3(lohd7leiis only 1/6 of that on the Earth?

  Object A weighs 40 N,i.cxvzk/ f.v on Earth, and object B weighs 40 N on the Moon. The Moon's gravity is i/.vkf.xv c,z one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposit0- m3ax(ag :iazjz(vne ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the na3max(j gv0z(:azi - rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a ledav167rd1yj;b 6qiss w0decnd u4 9 5fvel frictionless surface. A force F acts on the stacks5wbsdq;7fc91e1 d6 yj4dvnri 6a0ud , and it accelerates 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 staw w7pgl8u 6ow5cwr/2j nds on a scale in an elevator. What will the scale be reading when the eleww6rwjlgpowu/ 58 c 72vator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elei0 yx4mfmlw:8vator. If the mass of the person is 60.0 kg and the ele: i fm0x8ym4lwvator 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 elevator. a m*ht,u 5o4wkIf the mass of the person is 60.0 kg and u5kaw ,*m4oht the elevator accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. One fork:tzoh p pdugi005 35:syo9 xrce has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is the acceleration og50opy o:p0hzu iktd 9xr5:3 sf the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It b (a ) 9 lp;ahwwm,n.tbeja*i;is held in place by metal brackets that can exert a maxit,a);wje ;ahnp9lb (wi.*ba mmum 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 restsq44uw)qoei:zsbdwv ,ov;2 .w 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 the truck is traveling 15 m/wz iv:. u)dsoe4;qb qw2,wo 4vs, what is the minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, ifcb/cqrcs472 w m8:4v+kvma me M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the sys44v wc 2c mqc87er:kma b+/vmstem? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown57:/bu7h 8 zeh4vz 1.1su1 uyqz;qcuonzigej in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignn/: z 8ceu vohqy u1zuezuq71bh1.s gj;z57i4ore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of 100w 7 )+for2bcte N in a dir7wb2fteor )c+ection 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 smooth horizontal floordqwxm a 7e;iqxo1x9) qb.1uf( 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 forc7m(xqu f)x 1 q9id; xeba.woq1e on the box?

  A traffic light of weight 100 N is supported by two ropelo h()s2r2. awylvz z1sz cr7:v9lx *ms as shown in Fig. 4-2. What are thlls z a:1rv w22hr9o*) zx zmv7yc.l(se tensions in the ropes?

  In Fig. 4-2, if the tensions in t x-e8j 67fjft-zpym8she ropes are 50 N, what is the mass of the traffipf8x-j7zsyf mt -6e8jc light?

  Two boxes of masses m and 2m are in contact with each other o3e qe4dud mvu50x/dzay8d7 +b nos74zn a frictionless surface. (See Fig. 4-3.) What isa3uev 4o 8qzydu70eb ds nm/5d4z7xd + the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact zewzv 08s+n3f with each other on a frictionless surface. (See Fig. 4-3.) What is the net force +ze f8s3 wnz0von the more massive box?

  Two boxes of masses m and 2m are connected by d*vt4g) e uin- vnbuuj3(/5bvyf0m: ua rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tensionu:m/jyg-v4vu nu0n5* ti( vf bb eu)3d in the connecting rope?

  Two boxes of masses m7: yjwa71xs hh and 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massive bo:xh sj1haw77yx?

Two boxes are connected by a cord runnin7ky3 ;hoomp*i g over a pulley as shown in Fig. 4-5. Box I of massy*7hkmo i3;p o
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 kinetw7 uu/-ew;v 6mxu6l elic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectve xeu l6um6lu/w;w7-ively. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static 4fa) zp2gy;h qand kinetic frictions for plastic on wood are 0.50 and 0.g;azpyf4)q h2 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 surface in the +x direction. It slows and,h4 kjvu vx:ys52r ,,hcgxqq8 comes to a stop with a constan h,,4vc r,uqhsy2v jx: kgq85xt acceleration of -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontalwa8 r4czhr w x/4(xz jy)rkb3; surface is pulled by a 5.0-N force. A 3.0-N frictiobcxkja(r)r 4 zy /;w34hxw8 rzn force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at a rate 4ah)1w .j vuyqbcdj/y3cmer7;,)d wqof $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, a puck is given an initial speed of 4*tutulv uaolc--t3;a j04le 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck and ta3 u4e04uual-ct o *;tjvll-t he ice?

  During the investigation of a traffic k: z1 po2f/n)hjo 8hgtaccident, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing conditions. Estimate the speed gzt1)/njpo h fk2oh:8 of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked.ht.y7: fz /qxy20cfn7naj9wrj tj 86 k (See Fig. 4-6.) The surface between the more manj8 2a9 /7c:jtznkf qw y607fjhrytx. ssive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less massive box does not 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. .o3zary+: gl20il) kvm)neqn (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.kle+3avql 2: n)ygom.)i0 n zr 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 frictionlessy*f-ar qsir: 9 inclined plane. The plane is inclined at an angle of rr yif-q:9* sa$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angled1/b,6lzs /kl02 wl.-g j/pwg tseras of $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth iy3e niq;7ks( a/bz 74pgri2 ins u+ +pdcer8u0nclined 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 plane tilted a,a+5e j9mqupzs-4ie52 zd,8uqxsw j kt 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 pl7yh(kq 9v 68ao;eu7zpees 1o hql+zo6ane, at a constant velocity of 67o eok 8sh ovq(91lhze6z eyu;76a+qp.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 m slides dowjr1(c(tn n3 r wivk81gxci* 0in 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 m slides down a 5.3fho3he25nzyexp isc9 1p 0f1wquu 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 athq0+l*zwds x bfa 7 5/ki5rap-tached to the logd/l5a+a- 5qs bp0rw kz*7hfix makes 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 releas9whw 9vsd5(jwed from rest on a rough inclined plane tilted at an angle(wwj9sw9d 5 vh of $33.5^{\circ}$ 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 inclineru8ceie2 m/lk /ww/*wd plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this o/ kiuwrm/wee*lc/w 28 ccurs is q. What is the coefficient of static friction between the object and the plane?