Which of Newton's lawsf47crc9xzc-fp *bd : 0,paqg v best explains why motorists should buckle-up?

  When you sit on a chair, the resultant force h y+1x si:yw/ton you is

  In the absence of an ebylz:- jgnvkwun ; 802xternal force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are sudden/.u fd: saft2j(y-fm gly turned off, while traveling in empty space, the jtsu-af.m :dyg(ff2 / starship will

  A rocket moves through empty space in a straight linewconq. -2* butob o:1e with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that bw1eo* .oqo-un: c2btmust be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddgc -nd n. 7h) m6t5w 2jpc7pzio50srfwenly fall forward. You can imply from this that z7f.w c27dh tosj0p r5mwp6gin 5)nc-the bus's

  You are standing in vnbv :)ru,ws;/9orre a moving bus, facing forward, and you suddenly fall forward as the bus comes to rru b;n )or:wvs9,/vean immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the o)vy bk-sguzh8vdj*o(:-re+a+ hcy 7gbject.

  The acceleration of an objeafrsea2 0cuc 9*i11hnct is inversely proportional to

  A net force F acceleraxzatubv+/mod 3 m: */ctes a mass m with an acceleration a. If the same net force is app:um 3o xdz t/v*b/a+cmlied to mass 2m, then the acceleration will be

  A net force F acts on a mass m and 5pye ):q39 bzxvvhob ydh.p6( produces an acceleration a. What acceleration results if a net force 2F acts.z(:)3byhho6bq9vvpyp dex 5 on mass 4m?

  If you blow up a balloon, and then relean3siw5 upsj20jt mvlgh)5 ,a:se it, the balloon will fly away. This ltw 2 ins03u5)5vmhgja,s :jp is an illustration of

  Two cars collide head-on. At every moment during the collikgcz2pgx q(k zbj)o1+ s8xd26y,n;b y sion, the magnitude of the force the first car exerts on the second is exactly equal to qby x1zky6+;gz o x2p j,bdknc(2g)s8the magnitude of the force the second car exerts on the first. This is an example of

  If you exert a force F on anlqe g/7k 5e4xk object, the force which the object exerts on you wil elk745/qkeg xl

  Action-reaction forces +mv9fcbqo qk: b,fu4(

  Action-reaction forces arlc rgpp:3w(9+t q,zdre

  A 20-ton truck collides with a 1500-lb car and causes a lot of dam ew8uss;:-k,qc:fuz gage to the car. Since a lot of damage is done o,k fqz8w s: cs:u;eg-un the car

  An object of mass m sits on a flat table. The Earth pulls on t x5lf44q f/ ym+8hy u0bd-mrkrhis object with force mg, which we will call the action force. Wyku- l80/b mr yfmq4h5dr+x4fhat is the reaction force?

  A child's toy is suspended frd (utox.b5y2tom the ceiling by means of a string. The Earth pulls downward on the toy with its weighub5ty x.t2(odt 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 instantaneous forc0vkqx c4i, auc:qfb6 8e. The ball hits the bat with an instantaneous force, whose magnitu0f4a6ckuqc 8x,v:bqide is

State Newton's three lxfdbuqtj:fkin/w ow 93w-*6) wj:, w zaws.

  Mass and weight

  The acceleration due to gravity is lower on t tzk2plwf m24i: f:1tmhe Moon than on Earth. Which of the following is true about the mass and weight of an astf 1 2zw tmkl:t4mp:i2fronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a disv/7,9oo8e x l pd/d g0,kvkedwtance is

  Who has a greater wei2b fy*rki6g t.88hb-wuv ye3 wght to mass ratio, a person weighing 400 N or a person weighinyt -fw2 ib gh.868uv3*byrke wg 600 N?

  A stone is thrown stragv:b8ikt 26+x xqno k7ight up. At the top of its path, the net force acting on :k x2g7obtnx8vq6ik +it is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the scw)kjbh0e0i9 ame height. Ignore air resistance)w0 j90chik eb. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal vel8hrewp5go)hkas8oqc 8 )*vo5 ocities. Woq h wsre8g8h5)5pvo8kca )*ohich object experiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceili ,;plk 4ormn/rng of an elevator. The elevator is moving up at c lp,4rkor;/nmonstant speed. What is the tension in the string?

  An object of mass m is h eul nfci/m.(, sxa(7hanging by a string from the ceiling of an elevator. The elevator is moving upward, but slol(sei m7/. (,haxu nfcwing down. What is the tension in the string?

  The force that keeps yopem5y xt ebk,k0 sj ;k0-5u0avu from sliding on an icy sidewalk is

  It's more difficult to start moving a hu(x2y t:oftxkox4)73+ pq nj.ufme q2eavy carton from rest than it is to keep pushing it with constant velouym7o. kx 3 )poj(exxq:2f+tnuf2 tq4city, because

  A horizontal force accelerates a box f *dz8ttfu -bu1 s, )d*tnfk7ldxy x72lrom rest across a horizontal surface (friction is* k*zlxd)u27tt-8nx 1 fbylduf,t ds7 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 the box's acceleration?

  A packing crate slides down an inclined ramp at constant veloci xh2vvnhpm7u 1t(yp(1 ty. Thus we can deduyhpt( hvmp(1u xnv217ce that

  A block of mass M slides down a frictionless plane inclined at an angl2) nsyuj 6;u3uds-ux-n wr-qq7ojnw2e q with the horizontal. The normal reaction force exerteunxjjn37ywd -2q u6wsr-qs un2;)-o ud by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an ang yp.i x5t;sd,:kdu/p5 eq 1m 0soea*anle q with the horizontal. The normal reaction for5a/uk y1:nxi0 qpm ;.,ss* 5ded teoapce exerted by the plane on the block is directed

  A block of mass M slides down a frictionless planexqzn6n5p(wtbx/;6e e inclined at an angle q with the horizontal. The tn (xq 5ee66pxbz/wn; gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultai :twxb l*k5por) +xgt0 lq(7cneously on an inclined plane that makes an angle of 30e wit t5l0rwcpk7xg litx:*o( bq)+ h 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 azvrj::x v wdjk9nqm w59d)f+6pplied to the object, and it accelerzd)xq :j+9njw 6 dkv v:5r9wfmates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in j,q19 ;p-jvqdz ff;pqo j ke3)7.0 s. What is the average forward force onke,j p v 39j;f;1z-ofpq)qdjq the car?

  Starting from rest, a 4.0-kg body reac4w z-qjh8e(tf lh1n5thes a speed of 8.0 m/s in 2.0 s. What is the net force aez- 8( 54tfhhtnw1qljcting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires *z3e p(uqklvp-kr i*7a speed of 50.0 m/s after trave*3 zlk vk- ip(7uqrep*ling
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 thizsoy9 w.a .-we same force that you push a 10-kg mass from restiwsa z9-w y.o.,

  What is the mass of a person who weighsqp:.5ra 3)thsec wc.zr,( y8f0sgy yh 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Eartcze ed(,me1;t h where the ee1, te;m(zcdacceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the object okim9d*ojl,- *ct9e vr(k)bp eyki 8+tn the surface of the Moon where the acceleration due to gravityi+y*-pbk 9kd,m*etci ktrl8vj9)e (o is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and o m3w j0,qizv8xbject B weighs 40 N on the Moon. The Moon's gravm3i, z8q0vx jwity is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pullit5; bwe/w5dyi6 kpy)ux;sd;m ng on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean'y)uy e d bs/6wx;imw;;tdp 55ks 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 acts ontpuo lcc4z *.a;v2c /u the stack, and ;up/4*z ccval2t o uc.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 +te;j wn;yz0b2nz)ejin an elevator. What will the scale be reading when theb;j n+ zzjy)tn;e02we elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 609em8mu -zs n0q.q;gwk.0 kg and the elevator accelerates downward wizw80- numk em9sq.q;g th an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevatoouo* i*q6k+hivim;ce+ x30ue r. If the mass of the person is 60.0 kg and the elevator accelerates upward witqi*chee 3*iv6kiuu;o o0+ x+m h an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg o8vm) t03fc(dgl;gfck 6gq :e mass. One force 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 accelerateg 0(;:l8 36d tvgqfkg foc)cmion of the mass?

  An object of mass 6000 kg rests on the flatbrb9 lq1flkk2lr i:0-aed of a truck. It is held in place by metal brackets that can exert a maximum horizontal fkf19lqb2rl-a 0:i lr korce 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 the9e1q8qou mode.h2 4 -kj w3hmc 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/s, what is the minimum stopping time if the load is not to slid eoc.qku2meo1wh8 4qj h3-dm 9e forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is9;5lvf eo7i xyytt: o- the magnitude of the acceleration of the system? (Ignore friction and the ma y7lt y9ox5f;i:oe- tvss of the pulley.)

  In the Atwood machine shown in r31eph, 9l9: gods mjylno8f(Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension (psnd91emy,:8 ofl9l joghr3 in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force s+q bqbo,6 ,moof 100 N in qbso,,+m oq 6ba direction 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 floor b ehuy9) l/rn0gy2dh( with a force of 100 N in al0( 9b )dr2gyneyuh/h 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 the box?

  A traffic light of weigh-el robe,4d( tt 100 N is supported by two ropes as shown in Fig. 4-2. What are the tensdl br-ete4,o( ions in the ropes?

  In Fig. 4-2, if the tensions in the ropvh f3 w se;)p7vg ogl50g:aoem( 80ztses are 50 N, what is the mass of the trafghl 8e: azo;e mgwvps5g(0o3s tf v)07fic light?

  Two boxes of masses m and 2m are in contact with e 6 *m/+2l1nmb nml:d8abuj kfmach other on a frictionless surface. (See kdl1 m2 : m8nbmb+nfj/l6mua *Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact w-blzv-kqs 6dn(n+k:i ith each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more massive boiv-bnl+q : -ks (6dzknx?

  Two boxes of masses m and 2m are connected by a rb8n9 w:(kb netope. (See Fig. 4-4.) If the forward force on the more massive box(ne:nk8w 9btb is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4j :rl kc50v:xa-4.) If the forward force on the more massive box is F, what is the acceleration :cj lvra:k5x0 of the less massive box?

Two boxes are connected by a cord running over a pulle3lt qf 5aeoqw 2(,ddv1y as shown in Fig. 4-5. Box I of 5 (fo23,1qwlqedt vadmass
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-4d*ovzsbe 1az6b1i 2 efqg; v between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on thadoqegz2z6i- 4e1* ;1 fvb svbe box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50 anbi(t0ql uem4t4+x+l0g(kfm04 ;xf j ; vgh peud b mtlq;vgm+eilt4 gfk0e hx(fuxuj0 ( p;40+40.40,
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 su(u. d ,m db7rn1pi;nkho:wyg0rface in the +x direction. It slows and comes to a stop with a cdm dnb.7nk r0uw1o ,;(i y:hgponstant 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 horizontal 10le;hzkub+2 cgxpg/surface is pulled by a 5.0-N force. A 3.0-N friction force retards tbg/;ke ucgzx21p +h0lhe motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mashasuihe6* 9mxy d u,p4-x 19k.ojux2 vs, 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 6k n (nyu p-se4ift8wncop6)ad :;el ;puck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. W sn4eutfcd6-o:en 6;w )ny l;kpap(8ihat is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police +bz3i+ac mo0v find skid marks 90.0 m long. Theycm+o0 bv+ai z3 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 the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betweetiw j sk60j6,on the more massive box and the horizontal surface is smooth and the surface between the boxes is6o6t0j i wksj, 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. (See 4 nnrl h3iz+sgp 5,pz5Fig. 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 coefficient of stlz53n5,4inppr s +hgzatic friction between the boxes?

  An object is on a frictionless inclinevz 0y:ru,6yy:f d so5sd plane. The plane is inclined at an angl5uv ,s z6:rfydo0s :yye of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hilh:( (:9i9wxcfnkh gmfl that 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 planez2 uifukt5 1 yf8+sh;i 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 k),g,sflvhgzr :m+rfg( zo06hi:v;ytilted 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 planp:fgqs 5z k2,6:d qhnae, at a constant velocity of 6.06nkd 5pg:fq h:qz a,s2 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 c 5gnrvkn6*fuaxh a- ;e /v.v0slides 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 m slides do-+lg i8/b f ym9 hps-bj,ae(bown 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 z +texry,m. 3isurface. The cable attached to the log mex +.t mr3iz,yakes 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 20ysf z1ei.w2mh;e vz on a rough inclined plane tilted at an angle.e 20 z;wfshevmy21i z 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 o3( (gith+gbrctmz4iw +9s(knn an inclined plane. The angle of incline is gradually increased until the object begins to slide. The angle at which thincb(t +( tgs34i ir(h+9wkgmzs occurs is q. What is the coefficient of static friction between the object and the plane?