Which of Newton's laws best.(k;p0wl f0hvps xg,d explains why motorists should buckle-up?

  When you sit on a chair, the resultant forcdrf(q.ey-wkn ,qay/ ) f *u,8vyubeu*e on you is

  In the absence of an external force, a moving obgkzet2f w .8dr-g)e0bject will

  When the rocket engin.t *04bcj5hs3jtkes n es on the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space,kse st05 jn.34hbj* tc the starship will

  A rocket moves through empty space in a straight line with constanw:nx1uolc-i iz: s9mzo6.zb /t speed. It is far from the gravitational effect of any star or planet. Under these conditions, the forcen 6xsi.lioczm z: z9:1bo u/-w that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, faijrb-.jf 7xxept55, mcing forward, and you suddenly fall forward. You can imply 7jf r-5mb ,.xtx ij5epfrom this that the bus's

  You are standing in a moving bus, facing forwara3ubvkwj 2 )j0 lgld1;d, and you suddenly fall forward as the bus comes to an immediate stol3dlbvakg j1 w;0ju)2p. What force caused you to fall forward?

  A constant net force actkc /ml6:6 3 pvj7muvbvs on an object. Describe the motion of the object.

  The acceleration of an object is invzj uu7( 34h,dihs.njj ersely proportional to

  A net force F accelerates a mass m with an acceleration a.w:9mxn)-v hwf6 fd3m q If the same net force is appq6x:mfwd wh )-mn v93flied to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces 1f9 r: 1*hphk)b qeuczan acceleration a. What acceleration results if:9k h1)pzh *c1 ubfqre a net force 2F acts on mass 4m?

  If you blow up a balloon, ,zys/yy 6ocko u0t (;pand then release it, the balloon will fly away. This is an il;c ky60(zy o u/,tyosplustration of

  Two cars collide head-on. At every mg 4i/ 6ywd9osmoment during the collision, the magnitude of the force the first car exerts6d9/ mgwyi 4so 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 opera kt6 5* 3k)ea7jikbject, the force which the object exerts on you willa 3k j*ikpar )6et7e5k

  Action-reaction forc/ohaco; ,41xft a stx9zu,oo1es

  Action-reaction forces areqgzgj9t r:q5rn/:p 2u

  A 20-ton truck collides wig/bcd 9xd lk65az(f9qth a 1500-lb car and causes a lot of damage to the car. Sl5gd xqkcz (96bd9fa /ince a lot of damage is done on the car

  An object of mass m sits on a wg9ckfp23vdcy56m u9 flat table. The Earth pulls on this object with force mg, whicmwvgyc ufd p52963kc 9h we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiyxq;j 5i(j1 09t )fqgundmcb 3ling by means of a string. The Earth pulls downward on the toy with its weight for5fngc0;uqj9j3( xd myqt 1)b ice 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 forcgs jej c5y3;h.6 meu4ee. The ball hits the bat with an instantanee5uj m 6;gcehjy4e3. sous force, whose magnitude is

State Newton's three d fd9 ;0yd4q yjih+5bfjvu.,q laws.

  Mass and weight

  The acceleration due to gravity is lnl( .v;uvs+vsower on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surf. +vln;vvssu( ace, compared to Earth?

  An example of a force which acts at a duegf:hlfb e y1+3c uh+ols,r735 (j)ph wkp,ristance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person weig1.0abp -12jeu hhfdj3 6udp :kfhn5v xjd 50eau2hu11 b6hjvff:k- 3.d nphpx hing 600 N?

  A stone is thrown straight ub.l*wc 0t 6gco41p;9 zmbl ihjp. At the top of its path, the net force acting on c6ot;wbjzpi1. hm 9 0cb* lgl4it is

  A 20-N weight and a 5.0-N weight are dropped u obtrtqdsl /*kg:b(i-f59;q simultaneously from the same height. i b/;t t 5br:9ugqldo *f(-qks Ignore air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal velocitiestt9awu*, ,4sg ;fnpiw. Which object experiences the greater force twnig;uw*f, 94apts, of air friction?

  An object of mass m is hanging by 4wy7)1yjyqydw) enx *a string from the ceiling of an elevator. The elevator is moving up at constant speed. Wh4ydj y wyqney))x 7w1*at is the tension in the string?

  An object of mass m is hanging bnlp ywm o0c7j7h8 t1ntsj j918y a string from the ceiling of an elevator. The elevator is moving upward, but slowhs8moj11y jw907lt 7 tcp 8njning down. What is the tension in the string?

  The force that keeps you from s3brl. hte(+ifliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it isv gkyh7ep ,g.afzd 69tah;yo* m,8au0 to keep pushing it gv,,0ok 7;ez9h gyd.y8t fa a* a6hmupwith constant velocity, because

  A horizontal force accelerates a box from rest across a horizonta3hsgt4pi5 rg :o m3;vyl surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal forc4go ;:mi py3t3h5gvrs e is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant vsvbf . 8b4.jxup5c n yjo:1)zaelocity. Thus we can deduce jn c fu.j15s zob )8y4xba:pv.that

  A block of mass M slides down a frictionless plane inclines oy 7h4-.p;v2ygprupd at an angle q with the horizontal. The n-.r oy us4p;72vyg pphormal reaction force exerted by the plane on the block is

  A block of mass M slides down a f70a q:2j mfu6g4qd4o- doid eerictionless plane inclined at an angle q with the horizontal. The normal reaction force exertededj7oqdf6 0 4o i4q 2m-uegd:a by the plane on the block is directed

  A block of mass M slides down a frictionless plann8 l. n3r0oy dpm0.ndoe inclined at an angle q with the horizontan y0 ml30nond.o.dp 8rl. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclined plannx*w0q d3s+ axe that makes an angle of 30e wit+x xns03 a*dqwh the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N + m4 3oigdh0gj8 ydku(force is applied to the object, and it acceled o8g 3im(kuh4 jgd0+yrates 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 7.ii4 dg m-7zjc(0 s. What is the ave- (47mdgi zijcrage forward force on the car?

  Starting from rest, a 4.0-kg bodj/ ijecwn 87:ly reaches a speed of 8.0 m/s in 2.0 s. What is thj7cl/iw :8n eje net force acting on the body?

  An antitank weapon fires a 3.00-kg rvy)clb /zr fn,622tuox qi.a6w*od *socket which acquires a speed of 50.0 m/s after z.)io*qy*u6do,6 s al fbr /ct2n2xwvtraveling
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 mao t,e pq4d;w2ass from res,2qp eo;at4w dt,

  What is the mass of a person who weig-b i p; f5ihfl*o2tjo.hs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of t)h6p hzhts 1pfny0 /y5he Earth wherh5hp)nz6shy y/0fp1te the acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg-ro;h-4uho p vro9 f2b3 iue1e on the Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of that on the Eah4ipe;eh1 uvor3bu9-or of2-rth?

  Object A weighs 40 N on /gdt9v7;c. cta+d lkvEarth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the massek; lt vvc97+a d/.ctdgs of the objects.

  Sue and Sean are having a tug-of-war b;ob-*zr14u (fq3co*j hfrrbn y pulling 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 towano1r;3( o*b*rczr -fj4qfu hbrd Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless su .qqvua 10b8xuhywnc439r-ol rface. A force F acts on the stack, and it accelunr co4lh8 0ua.1yqq vwb- 9x3erates 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 inn q,xrtcyl2 je7 88x+nky*b8 v an elevator. What will the scale be reading when the elevator is acceleran x+,n8rb yylc2vj eq*t887xkting downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If t24nlje 7qqbfy/d 21l*jiym.yhe mass of the person is 60.0 kg and the ele7lynl4 q2jy*/2b yqidfmj .e1 vator 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. If the maa 2a*wxh6jhn 3ss of the person is 60.0 kg and th32a xw 6hjha*ne 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 force has a magnitude of 8.0x k*7 *;gbj3u+gt kjyv N and is directed due north. The second force towa*3b v7j j+u xgkk;t*ygrd 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 flatbed of a truck. It qb tz;2)tk2o vis 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 theo2b)tv2 qk;tz 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.m q4:bqit48f p It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the truc4 qbi:qt4mp 8fk 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 Fig. 4-1, if 0csz9 b1i(h5pt m4bkm M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration o s5bbph(m c9k t4i0m1zf the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine so,hn 2,t+n9m 3 vmlgmvhown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (l ,tv3ghmnmmn2o, 9v+Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizow)yb48mj7 dt 2cwbxq5 ntal floor with a force of 100 N in a direj8cqw) dwtb7 m5yb42xction 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 hoge iq* )esrh82rizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and theq2gishre8*)e books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown iua0ku1 5kxv 5an Fig. 4-2. au x55vu0k1ka What are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 5fwb,7- q5jzx1:g cxvn0 N, what is the mass of the trafficjf g7vwbnxxz5 :1-qc, light?

  Two boxes of masses m and 2m are in contact with each oebe odc1 ;*nl28yb 2hcther on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more massive boxb dehl *c; o2b21ey8cn?

  Two boxes of masses m and 2m are in qeppoxp8q1:4/ +4fni sjh mt /contact with each other on a frictionless surface. (See Fpqotm4p+i x84q h/sj/:e f1 pnig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected byq(if)fh0vgv8trr (0 6f yk2i j a rope. (See Fig. 4-4.) If the forwagj 60q0i (rv8)fvf2ir kty h(frd force on the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4319 gab+m7 kvueb7cyu .) If the forward force on the mocu37am+ vby be gku179re massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord ru*; *01 4ay5x1ste pthinqwfnpnning over a pulley as shown in Fig. 4-5. Box I of ma1y0 n5*tfpa pqnx ;whte* i41sss
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 staticd1nay9el2 x1g and kinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is ad en19lx12 aygpplied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.5zx(kzbdd cw :mn3v0;2a 5ccy(1,uox )g) wjzo0 and 0. ) o,0 aj :uzcv)5;g (w1ybxm2d on(dwkcx3zzc40,
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 s9ie-3m:zzw nz psr: -qurface in the +x direction. It slows and comes to a stop with qpz-:m 3res- i9z w:zna constant 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 surface is pulled by a 5.0-N force. A 3.0-N0 9b0i,ntsg5dx 9 enh)leyk4v friction force retards the motion. What tnb gkh5 ny0e,0svl4 i99edx )is the acceleration of the object?

  A horizontal force of 5.0 N accelerat 5yb)5mpz +0u tam4pxues 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 speed of 10 m/s. It slides 50 r4pifu5/+l 2c6xs jhr m on the ice before it stops. What is the coefficient of kinetic friction between the j52f+up rilhc rsx/46 puck and the ice?

  During the investigation of a bdee: q gw1: n1jj4b)ftraffic accident, 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 f1eg:b)jd 1enwbqj f:4or the prevailing conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See F*o 0y rcc.h prf)h;vr3 bp0f)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 static friction force on the hrh *by ;oc r0pv0)3rfffp.) cless massive box?

  Two boxes of masses m and 3m are stacked. (See Fig.v0pt4yo zc 4.w,eg 7jr 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 thjwoc4v t.g,z7p re y40e more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is in5bt1dqg j, 8lczbuz-nm4ye,ck (o;:a4x 1hqxclined at an angle kgcmz e1(bhxz 8nj-y4uaq4,o, tx1:; dcbq5 lof $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that mu3 b5likkf amfc+2d6)/2 djk fakes 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 p;96e21t37cs8 0cvrpqmhpluh9z dj dplane 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 at an ang tdg)tdfv9;5qip/ 8j8d rw 7rfle 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 hyg/t3pp y5 w6:ox8yzdown an inclined plane, at a constant velocity of xyzy3o 6:8w gyht/pp 56.0 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 slidesv9+f aga2p vx .3lxke1 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 sli p de5jxwc59gj q)of)tj k.p9ev.8wj 6des 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 c /, v eel96o*fgroqn-wusx2q, able attached to the log makes ango e*x ,6 wrsv- qn2u9oqf,/el 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 ;6j o6jal*/u4r fdyrrs401c srg5fqion a rough inclined plane tilted at an angle rcfifj; uy6q0ogrl5r41daj 6 4*sr s/ 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 wx )sak:s-a om5l8 p/finclined plane. 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 friction between the object and the planoska5l s )8 -mwx:/fape?