Which of Newton's laws best blj:p lz6l ok4)d)e) bh2tr8qusiu,pw 72m z- explains why motorists should buckle-up?

  When you sit on a chair, th/qultu2u:117rohey6 d (r orr e resultant force on you is

  In the absence of an external force, a moving o6r ag wc/4l/wpbject will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned off,,3m8lt jmyry-b.s l /w while traveling in empty space, the s,r.lmj-y/3t lw smby 8tarship will

  A rocket moves through empty sp,mfp :vuw3 +ghace in 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 to su,m:g+wv3 hp ufstain its motion is

  You are standing in a mov 09o6y0lvgs tming bus, facing forward, and you suddenly fall forward. You can imply from this that ty mtvg9l o006she bus's

  You are standing in a moving bus, facing forward, and au(e5nu/i; ao you suddenly fall forward as the bus c ;en/oaui( u5aomes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objecegy:ghmp(t-t2zm v f30 0 e8smt.

  The acceleration of an object is02th pxcjol-p ia2v*o n0o,z4 inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the same net forcqg : .1 gjbn h6(qr .5vo.h*+hemeqmxwe is applied to mass 2m, then the accelerationqhegv.qm*: +x h6nrob1jhwm.e. q g5 ( will be

  A net force F acts on a mass m and produces ,fnq)tg0 1vl;bunh4(d vx ea- an acceleration a. What acceleration results if a net force 2F- 0x(vau)dfenlb 4v1, n;htqg acts on mass 4m?

  If you blow up a balloon, and then)s.*9wb a cpba3p2pnb release it, the balloon will fly away. This is ac) s.9bapabp23wp bn* n illustration of

  Two cars collide head-on. At every moment during the collision, the magrp:qn)hv n z 7g,)ipy(nitude of the force the first car exerts on(:pr, i h7p q)ynnzgv) 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 object, the force which the oy1bx.*5mdo djbject exerts on you wiojx ybm15d *.dll

  Action-reaction forcesp cjw11 z,dxuy.5da8i 9fv;vbb l8gl8

  Action-reaction forces aregkmaw ylek -chzo- 1d;-:6aj kqs.91w

  A 20-ton truck collides with a 1500-lb cargwca*6pcm -p;.o+cz bljd0mhop t6 2/ and causes a lot of damage to the car. Sin6dzwhgl o a0ppjc* 2.c-c6pb+;mtom /ce a lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on tc4g(otwj0 q i2his object with force mg, which we will call the action force. What is t 2w oi0g(tqjc4he reaction force?

  A child's toy is suspended from the ceiling by means of a string. la(b -htzq;o8mvg7b;r om 9d 7The Earth pulls downwarmz7a oq-d;9 og (h;8vmrl7b btd 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 axy+y ij:1qf;;7t g-mvah1 pnr 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose mag7;v+tj f:hax mi11y; -gqrynp nitude is

State Newton's three la8y pa)ky5jeo jf.9 mh)ws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Wh 1q.txsx ubs g4q:8f.qich of the following is true about the mass and weight of an astronaut on the Moon's suxbt8 q. qxg: s1uq.s4frface, compared to Earth?

  An example of a force which acts at a 2 /:hksmiiu; zdistance is

  Who has a greater weight to mass ratio, a person weiv vce- cbp j) 2)gs.dq0hmw51ye;mtv7ghing 400 N or a person weighing 600 dwmevc5) s)-emvp0h b.qcv; 1y jt72 gN?

  A stone is thrown straight up. At the top of it; w/x8k yqk:y udj4s89dkq7 qcs path, the net force acting on it isy8 k/kx9cq :ysk;w7udjdq q84

  A 20-N weight and a 5.0-N weight are droppe5x m-y 2jrbt.dd simultaneously from the same height. Ignore -mt.ryjdx2b5 air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective czr2,fx+mj 0hv+3vzd 9eny6h: m4rnfa r.p n1terminal velocities. Which object experiences the greatep4rfmnn0d:c,3z jnhea+6 v.2zrh+x 9v1 rmyfr force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevato ej ;fh,jyqc:*h-a4wn r. The elevator is moving qchh , fn;4a-:wjy je*up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elev wm:l3j0u./u1wybq ky nl+o32gem( yq ator. The elevator is moving upward, but slowing down. What is the tension in the muul q/ynl10 e3qk.gy(w w:jm yo+b2 3string?

  The force that keeps you from slid f0ex4 vnv;cx3ing on an icy sidewalk is

  It's more difficult to starwdi1g6aly gdtkxz5l f cnr :c-7rr5y;l; *70wt moving a heavy carton from rest than it is to keep pushing it with l5w zc;y dgr*kn c67gix dt-wf1a5:ylr;r7l0constant velocity, because

  A horizontal force acceleratewmrl/+;b-is/g(q tp *u8jou u5(bokr s a box from rest across a horizontal surface (frictiob( /u;q(kor58r+/u*pw ul- st gjibmon 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 the box's acceleration?

  A packing crate slides down an 3w q /*j7okay3wv6aruinclined ramp at constant velocity. Thus we can kwvruw7 q3 /3*6yoaaj deduce that

  A block of mass M slides down a frictionless plane inclihn6 pgx zq k lgml,q-z(6k )kq1.(5ifoned at an angle q with the horizontal. The normal reaction force exert.-ln(6k gizqkq(6lg5p)f hx, zoq1mk ed by the plane on the block is

  A block of mass M slides down a wdzn )llrs5p8 z 5b /+er9ehb7frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted8w)z e9+nl lb5 ph/es rbrzd57 by the plane on the block is directed

  A block of mass M slides down x;.6vlfa. c nbw)j x:xkiv)r 3a frictionless plane inclined at an angle q with the horizontal. The gravitational forcevc .k b)vawij6x:fxlx.3 r);n is directed

  Two toy cars (16 kg and 2.0 kg) are released si:65)krg zl9up-b z ddimultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their accel d6pulk-5gr9d:zi )z beration after being released.

  An object sits on a frictionless surface. A 16-N force is applied to the ob(u+z6v4y1oked-s z 3wa/moamn jj)q0 ject, and it acceleratesmo akzv/e40- (wjujo 1d nm6zsay +)3q at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 k7dli oze9 06.9 yhf x5cw.oqfwg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward forq9 fz 5w7dclhi9ofe60w. .oy xce on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What ijm45ymrbr7q:(8f ox gs the net forxobm4qrjm (785yg f:r ce acting on the body?

  An antitank weapon fires a 3.00-kg rocket3sol nmyc)8 w2 which acquires a speed of 50.0 m/s afte cw382mlos)ynr traveling
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 yfrr7, 8gs9b 6 rnhqhg5ou push a 10-kg mass from rest, 6rrrgg7bhn5qh9sf8 ,

  What is the mass of a person who weiq 1j.ejfk,y.l ghs 110 lb?

  What is the mass of an object that weighs 250 N on the surfa(iq hu7j0dsf :j ps *7vy-b)qcce of the Earth where the acceleratio( - s7y0udqj:fhb ic7q)*jp svn 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 th:k38cx qrbj v+xj*nq u-ny0)fe object on the surface of the Moon where the acceleration due to+jvuqy3 :xcxqn *fr- k0j8n)b gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N q cuud+fax7/s3m5*m.spj zt, on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses ofs 5m uf qatc3um/j,d*7.p+xzs the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a bs3(i;zke3 ctplvy 5swt 229k5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward p9kzlw 3 iy 3(se5tt2b2cs kv;Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surf +7 j v1pkdgs13.zvegy.tgd(hace. A force F acts on the stack, a7d1(stvgedk gzv hg .j. p3y1+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. What will thenm 7 iui m63v.wq54shr scale .q iurmis7v4wn5mh 63be reading when the 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 km4wo1d/70ovq jb4 y o60.0 kg and the elevator accelerates downward kyqv 4w/7ooo1d0jb 4 mwith an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If tffi6zl 3 b;e;hhe mass of the person is 60.0 kg and the elevator accelerates upward with an accelera3if6l;b; zhfe tion 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 magnitudexz, 6, +0qgdcfzg e0p9cm ;e lv.miz6j of 8.0 N and is directed due north. The second force toward the east has a magnitude oe,q 0x zijd+m l9f;.v6 c6pgzce ,0zmgf 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests jzkx, 911k/chuk8uwpb (j) wq 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 tra)xkh 9jwq1,uku8j(z /kc wb1pveling 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 flatbeds oc,byr9w 9(v3q6x ov of a truck. It is held in place by metal brackets that can exert a maximum horizontal force o(xs939 o,cqy 6vowrbv f 9000 N. When the 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 in nk+mpm;,lh ) jFig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is tn+;pj h,m lm)khe magnitude of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, i.xq 2 .,lxgoiqf M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pulley.i2.q q xgx.o,l)

  A student pulls a box of books on a smooth horizontal floor xi 0v1kul9n7o with a force of 100 N in a direction of v1x079 ulnk oi$37^{\circ}$ 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 bontk2 94m6qhqkoks on a smooth 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 thh9 qtk6qn4km 2e normal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown in Fig. + (s+1rsl jivtp 1+a-l6h(fmyq n5dnu 4-2. y1d q l1l isj(+m(5 -n h6+asvfpntru+What are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes a ( twu41r;xexq e1bt(zre 50 N, what is the mass of the traffqw1zt4u(bx;r(txe 1 eic light?

  Two boxes of masses m and 2m are in contact with each ouwr4 wo7j; wq1ther on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more massiq1r7 j u;wow4wve box?

  Two boxes of masses m and 2m are in contacwcb+ bj75,vzd/n g-. bz)v/gm zul8dr t with each other on a frictionless surface. d , bd)r l z+5bc8/z/mg7-.nbvuvgwz j (See Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are cf+e2a ra7;h+1bcvnvaonnected by a rope. (See Fig. 4-4.) If the forward force +n avb;7 2ehc+af1a rvon the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connecte932 knhj kj5 e./czpsyd by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of theknpj9/ec 3k5j. hsy 2z less massive box?

Two boxes are connected by a cord running over a pulley as shown in Fig. 4-5. 5,vdebh2r pa73pi/ lfBox I of m h5b,a fdpr7e2li vp3/ass
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 between a 3. xidyv yn:,sq0zy9 .e,0-kg box and a desk are 0.40 and 0.30, respectively. What is ,,eq:0nzy xy9sdvi.ythe net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictffb2x2 ni rlp04jlf) 1ions for plastic on wood are 0.50 anf2fipxr nl 04 f2jl1b)d 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 surface in the +x direction. It slows and comes m5jq70, drgspd+s yrcy5h /c5to a stop with a constant acceleration hys+dd pym /57c5q,jgsc 0rr5of -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surface isr7-fx(t qly*.icjbzahs2 ; ;lzb5 6aj pulled by a 5.0-N force. A 3.0-N friction fo5s62zh-fyjr jat7a b.lqc;x b; i*( lzrce retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N 3lf/98gqkje m /n hr1a6 g2jptaccelerates a 4.0-kg mass, 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 -blte1uht1 )6rs kfcxeosvl0 bjj)5 y6c*,v7 speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puckx1h-ybcu1eolr 5ks6cevs7* jf) jtlv, t60b ) and the ice?

  During the investigation of a traffic accident, policek52wav if+f f4sth,*a find skid marks 90.0 m long. They determine the coefficient of friction bwa+a*f f 4vf5tk,s ih2etween 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.) pucx7*v w3*n3/w54yoxnf, itc(dwf u 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 cfct*3x3u noxdvp 5/ iuyn7 w 4w,*(wfbox, what is the static friction force on the less massive box?

  Two boxes of masses m aa 1m;+cs :yebm7f jmb;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 s;7m cjfbb+ysa:m ;em1lide on the more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane ihm+0 j-kvn/6hmx-ik i s inclined at an angleh0k/km+xn6j vi-mi-h of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides : /p8jrv7bt re*+rbftdown a flat hill 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 plane with an aps56/8 b)vvevhr kn -qngle 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 tilth 05eue jl5y478 t ,qf akg/fmpo0q.vbed 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 dirrf +s*f7t l4pifq*(own an inclined plane, at a constant velocity of 6.( *7t4 flfriifpsq*r+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 down a rou h9at lp/r2iak67kg v 0bb7xv7gh $37^{\circ}$ 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 q opanjrzjw*j6/ 2q/f+ y cs(qv-fq14 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. at/w+a2bex*a-h qy+hThe cable attached to the log makes an anglx+ha 2yae*-/+ w aqhtbe 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 i-fyt ors(cp df0j4a -4nclined plane tilted at an angles4 0c roy(atpf jf--d4 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 inclined plahc0rmxq 2io *j.8v.sene. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static frictrxq. sc2*h o0mj.8i evion between the object and the plane?