Which of Newton's laws best explains why motorists should buckle-up?t8n3 5 t .y,fc: bixrz4t9cvpt

  When you sit on a chair, the resultant force on you imnow,b;,j;4t( c atx 3s1otjws

  In the absence of an externa2sj,y0f fi o)tl force, a moving object will

  When the rocket engiekusr)) 9y4i 5ofp 3cgnes on the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the 9 4sfpur c))ke5ig y3ostarship will

  A rocket moves through empty space in a straight line with constant speed. It bcouuf ( lz/es28lk1dkoy3( / is far from the g o(3/y 8ezkk(uu/c lfbdos1 2lravitational effect of any star or planet. 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, and yodm;fl9v 5q/1ovd hc8gu suddenly fall forward. You can imply from this that the bus'd c;9 mqf8 l15vgvdoh/s

  You are standing in a moving bus, facing forward, and you suddenly fall forwardb1rbp 1wx2pmlwl/pl3z / 0 p xkh5(e0t as the bus comes to an immediate stop. What force caused y2bmk zt x3(lph rlbp50p/pwwx10el 1/ou to fall forward?

  A constant net force acts on an object. Desciz2ii nqa 2+3l fov48iribe the motion of the object.

  The acceleration of an object is : q .g:*/.ljhfjpo0r zlm/ayni12f fk inversely proportional to

  A net force F accelerates a mass md,aar9poq,x5g 0f i (y with an acceleration a. If the same net force is applied to mass 2m, then the acceleration willqp,o, yx95gr0 (diaaf be

  A net force F acts on a magd95pocor p/mg).at8 a;jruel; g;2 yss m and produces an acceleration a. What acceleration2cpa;t r gogu)orp; 5.je;9/myadl 8g results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the ballog )+3 np-pg y47tqv-64d;jgypkrhmlion will fly away. This is an i grm 4p l7jq+) n6g-vt i3pd;y4khpg-yllustration of

  Two cars collide head-on. At every moment during the collision, the magnitude opl;+ she://eqzog-x uh0u hv (rx a;b6dt5z7vf the force the first car exerts on the second is exactly equal to the magnitude o:;e5 v 7+hxzt6/-hs ua(uzxl;d e/ hobq0gprvf the force the second car exerts on the first. This is an example of

  If you exert a force F on an object, the force which the object exe2 xi3xz;t8rtlm -k5rm rts on you will2lt r; 5mmrzx ixk-t38

  Action-reaction forcejisbyh0h6)k m ei(xp k0-k8q:s

  Action-reaction forces are+*bw ao, (doz-fieg-o

  A 20-ton truck collides with a 1500-lb cpcs+dwb6: -rcgs y d69ar and causes a lot of damage to the car. Since a lot of damage is done on t+dc6:bs-pc6 dwrs9yghe car

  An object of mass m sits on a flat table. The Earth i3 x7zu)591rfitbv)83 k9nmb jch msk0uqz 8lpulls on this object with force mg, which we will call the action force. What is the reaction force0u5hs 9lnkbzvt)k m8xf7 m31 j iq9u8c)b3zir?

  A child's toy is susr up 8oepl/5g.bl.p i)pended from the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is teogripl p.bl/.85 )puhe "reaction force"?

  Your bat hits the ball p0td+4 mg (; nt9lsgqdditched to you with a 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose0 t g9(s ndqmg;+ddt4l magnitude is

State Newton's three leb - el:d2m6pffgu17 m1 -;,1 sv famc7agyvxraws.

  Mass and weight

  The acceleration due to gravity is lower onry) w ihi;5;oa(eq z wyf48)qj the Moon than on Earth. Which of the following is true about thi( y)q)w8y4ozw; rje;ifqa5 he mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts aalf)s49qe2+oo( q lgbt a distance is

  Who has a greater weight to mass ratio, a person n 9fxq:n* g-bv(f+posda/7g(o yd et .weighing 400 N or a person weighi- *d7ad+ /se (pftox :nngqvb.gfo9y(ng 600 N?

  A stone is thrown straight up. At the top of its path, the net force q;7eg,sv nsz//d tj-y/ 2mepnacting on it msynpqe n/; /z27ev/d-gsj t ,is

  A 20-N weight and a 5.0-N weight are drhahv lv wu7 czx p/993cp6zyn5+i/ci(opped simultaneously from the same height. Ignore air h+/i9v/wnz59 (7xalichyc u pv6 3pczresistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal f 6ko+ mlyg+kz0f;9 *m j3yqqhvelocities. Which object experiences the greater force of air f+0 og;+kylqzqk3 yfhj *mm69friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. 0cuk- :1(a g+aaox negThe elevator is moving up at constant speed. What is theg+n cuakg(e- oa :10ax tension in the string?

  An object of mass m is hanging by a string from the ceilingk2 i jo(k9p lq +k.*jvqu)h1o l*ack0z of an elevator. The elevator is moving upward, but slowing down. What is the tension in the string?c)j*2iz* 0kk.jll1 qu9okpkhv+(q ao

  The force that keeps you from sliding on an ib a5nap (a+yo2 8b khghggm*66e rh:1bcy sidewalk is

  It's more difficult to start moving a heav3; gfs zsv:k-n1/a xzzy carton from rest than it is to keep pushisf-s3n/k az1:z;gv xz ng it with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surfac+cb7fz x.*qcxt9 a5ch e (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal force is doubled. What happens to tta9+fchbc5q* 7 cxz. xhe box's acceleration?

  A packing crate slides down an inclined ramp at constant v.qd 2om22jgq relocity. Thus we can d2g 2q2d rmo.qjeduce that

  A block of mass M slic m1xus 4pr,q+48k xzydes down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by thezr,+px1k s84 4u ycqxm plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angle q7c8vrk9fp g u3 with the horizontal. The normal reaction force exerted by the plane on k3g pu78rcv 9fthe block is directed

  A block of mass M slides down a frictionless planu2.gr6 r)qt5:aiy pj je inclined at an angle q with the horjjr 5r.):6gtp q yiu2aizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneogkf m6 3kag1*tusly on an inclined plane that ma13m6 a*ftgk gkkes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied to t/urs;v9)y3ueoy)y 4drhxv b7 he object, an 9vsvyx r r)y;u3oh/ye)b74udd it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 3/ q/1c (flldn6kiix fkg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward force on the car?/f1kl /6( qifclx ndi3

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. hy4sl7 kb: vc+qf7i hk vm0/: m(bflt* What is the net force at4 /k bfq7ms:7vylh ik(0:+ cvh*bfm lcting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a spe-9 y8byd8nfu nt n/w5.cm9 2 ubva1nnted of 50.0 m/s after traveling /t vdc-bnb21mnwnn. y5uf898t9 unya
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 t kypn1jjx(-1u4t ;ou ic36oazhat you push a 10-kg mass from rest- j o act6uy;pju(31k1 4xiozn,

  What is the mass of a person who weir4hixm ff ,-woepyb-0+4tz ( i/xzb0 qghs 110 lb?

  What is the mass of an object that weighs 250 N on the surfac )zyl/t2yqp zn; ia2y(yq(8 efe of the Earth where the acceleration due totfy;ipely) n 22 qzy(y8zq/a ( gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the gh-7 3x1kyi lkEarth. What is the mass of the object on the surface ofhkg- k37ylix 1 the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. The Moon'l) ze gjc3dj/d bi/g71sg)i/ 3 e/gd1dcjlj7bz gravity is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 7u:mu4k-m6sdo yomf y*g)8g p 5.0-kg rope. Sue pulls with a 15-N *mo4 pm -)k mufudygsyog8:76 force. What is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F act1/z+ vvdf x1;q6sm xncs on the stack, axqvd61 cms1nf zv;+x /nd 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 stands on a scale in an elevator. Wculk) k i++m u.b7r,dthat will the scale be reading when the elev7ukk.rub md+) , +ilctator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the zk.ydx* r+o 6f 5ww4cnmass of the person is 60.0 kg and the elevator accelerates downward with6ywcr+4o .z kx*wdfn 5 an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. Ifa5 cj 5zua11bi the mass of the person is 60.0 kg and the elevator accelerates upward with aabac1u1 iz55j n 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 force has a yb/jk m;7u70lhqsl 1r 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 of th/bmkh1 lu ly7jsrq70;e mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is helyk km-brl18 v 09a)mqcd in place by maymb-01kcr9) q v8kmletal brackets that can exert 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 rests on the flatbed of a truck. It is held in d1/* 2 twrxhuouc1ot(place by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, what is the minimum stopping time if the load is not to sloc2xt1u(hd rt ou*1w/ide forward into the cab?

  In the Atwood machine showo 8c,zu55xcexwj3 z1 mn in 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 ao 5exz83xw5ujccm,1 z nd the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if +l+ y5plhywj 38twv/wM = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pp+hwl/ 35+w yjyv8ltwulley.)

  A student pulls a box of books on a smoo. 4zu/2iu7q9v uurkxr th horizontal floor with a force of 100 N in a directioqx2vuzr497 /u iru.k un 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 b 1s-o z*u,pjifs7g+ha smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. Ifb 7giz1 hups*os+,f-j the mass of the box and the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N isnfy-( dk5mp f ar-v, xccks1+( supported by two ropes as shown in Fig. 4-2. What are the tensions in xkdc+fs(mnra1vc -y,p 5 k f-(the ropes?

  In Fig. 4-2, if the tensionsu so2-pz+kxxbr 5-8w4q2 beb,on jt8g in the ropes are 50 N, what is the mass of the traffic lw x-58,k4or8ton g p-+qeu2zbsbxb 2jight?

  Two boxes of masses m and 2m arez) b*d zl,gihw,rz1w1 in contact with each other on a frictionless surface. (See Fig. z 1r)zb1,*iw lgh,zwd 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with c7 * cc+h 8tpfzsifqf;c 0ew46each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more massivfef0cfp;8c7w4c*htq c i6 sz+e box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.43jdqdmt+. jfd hzd6 -) If the forward force on .4dmd qtj3h +ddf-6z jthe more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m arey/, gk*lz,7(akp:oa3 i f lned connected by a rope. (See Fig. 4-4.) If the forward 3d(lp e i nak,g alyf/,*:ok7zforce on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley a(r: n lu1laf,bs shown in Fig. 4-5. Box I(ub :1fa r,lnl 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 kinetic frictions bu*9 uwnl) puq +ib2w0zetween a 3.0-kg box and a desk are 0.40 and 0.30, r9l)+unzbw0q 2puw *u iespectively. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of stai nyxzsv q, 7lqu;9l*3tic and kinetic frictions for plastic on wood are 0.50 and 0.4 y qv3nls*qu9; ilxz,70,
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 spnu -2h 9gqvtdpi76x asgf+ 70urface in the +x direction. It slows and comes to a stop with a constant g+7p 27txa-ngdi90puhs fqv6acceleration 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 horizontalf:* huxi;op5uyghn7 ) surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of5ou ;:x)yhh *7ng iupf the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, frv( 3h cy fk ykzud2p7r(vi(25rom 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 speed of 10 m/s. It slidb kp*ji-q ;en1oghy4 ad2( ci3es 50 m on the ice before it stops. What is the coefficient of kiney(kdi4p *oan2- g1;ecbiq j h3tic friction between the puck and the ice?

  During the investigation of a traffic accident, police find e(5 gvl:/tef xj(8xikskid 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 of t i/ke5fg(e xv:xjt8(lhe car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-lc )q0v-n9q23 s oyphgqz5;;ofnplb66.) 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 nsqyog obqhn3) -f0l 2q6c; 5ppn9vz ;lot slide on the more massive box, what is the static friction force on the less massive box?

  Two boxes of masses m an,rv lc., v(yqocg:t+ nd 3m 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 not slide on the more massive box, what is the coefficienr,(,g:c tvyo .vcql+ nt of static friction between the boxes?

  An object is on a frictionless inclined plane.hc8ikykk8p; 6iiym)- The plane is inclined at an angle o6)p i ;yi-k8ikcm8k yhf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill 9(*mrwnm c2v rthat makes an angle 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 inclined plane with an az4p3fji 0,ey wngle 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 at an angle ovj k3fejef eqm6z87(3f $35^{\circ}$ 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 inclinedd b y2)izi,t6j plane, at a constant velocity of 6.0 m/szi y6tbjd)2, i.
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 down a roy:3 e z64qb4nghx+mw s1qauw4 ugh $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m sv 5*i: ue(kmevlides 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 ssr fvj) a;w;v5qt3 a-e27* qzv0 npcyiurface. The cable attached te yi -j;qavp )vza2r*5qtsn0c37; w vfo the log 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 released from rest on a rough inclined plane tilted at an ang.qf;9ds3suh t9/wp xrle of suw9h rqs. tp/x9d3;f $33.5^{\circ}$ 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 of incline is gradually +pgsqfk lw13qe0h v6o4m 1wy)increased until the object begins to slide. The angle at which this occurs ise3pf1lq46o k y hg0)q+ww1mvs q. What is the coefficient of static friction between the object and the plane?