Which of Newton's laws best explains why motorists should buckle-jafgo( n-0(wvup?

  When you sit on a chair, tb 6k/d2lxm 0wq :-fdcihe resultant force on you is

  In the absence of an external f 9, (3a3jkhltpzmok:gorce, a moving object will

  When the rocket engines on the starship wyw wis ,jw3comk/0j8p .pp7 7NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the,p 0 k p w.w8wymisocj7j/3pw7 starship will

  A rocket moves through empt1fmoqg)f. d3i y space in a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the)im3f.1 qof dg force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, faciuch2o1yo 4pnel y6 ,)kng forward, and you suddenly fall forward. You can imply from this t21 p6yk e4l)n,y uchoohat the bus's

  You are standing in a moving bus, facing forward, and yeo4c2 qz tcu;/ou suddenly fall forward as the bus comes to an immediate stop. c u;z4tc 2/oeqWhat force caused you to fall forward?

  A constant net force acts hw*ecplm 0 x;(zjd17xon an object. Describe the motion of the object.

  The acceleration of an object is inversely prqwc 9 2r*en +ju0f5jbe7nl 9xh1)f qgroportional to

  A net force F accelerates a mass m with an acceleration a. If the sam2j;5lhd/cwcp64. xcm0 sduu ee -e)cb e net force is applied cuxme; p5/c)s- 2dbewc du0j4ec 6 l.hto mass 2m, then the acceleration will be

  A net force F acts on a mass dioi +plym8n6l3 32 9oklyc6hm and produces an acceleration a. What acceleration results if a net force 2F acts on mass l 3+ pnok8 6l3li cdyo2yi6h9m4m?

  If you blow up a balloon, and then release it, the balloon will fly away. This 1w cp9-u +jw)ipv u htkwkn776*c 4zocis an illupu9 w7kctwn4j-1 c7zkhip* cw+uov)6 stration of

  Two cars collide head-on. At every moment during the cqpe1k)5yijwfthw , l6 ;n5+z7jm-i ovollision, the magnitude of the force the first car exerts on the second is exactly equal too; p, 7e1i-vyl56wzfn+5 wjkhjqmt i) 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 x) )xhzo5 s :jj9npn8mforce which the object exerts on you wiln) ) 85s9jh p:zjoxmnxl

  Action-reaction forcens :a(93fue lho7x b-hs

  Action-reaction forces ca .nw-/)eoie g3hw3s are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to th- 6vbo7fsrd3w7dj eq5 e car. Since a lot of damagfv7 rj5 boq6d7-de3wse is done on the car

  An object of mass m sits on a flat table.+ z2cr bmi/kb4 The Earth pulls on this object with force mg, whii24rmb/z b k+cch we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. Tm.y wqd(7 hsf) i4d-l)8fce akhe Earth pulls downward on the toy with its weight force of 8.0 N. If this is the df8 qcmf4 .(7ywdla)e k-)his "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantanwjpo z:gmf n;h7jnmv(2 ) ve1*e .iy3fz /o9yzeous force. The ball hits the bat with an instantaneous force, whose magnitude isgn;y9imfym3:z p *jwho)o z1 /e7z.2e(n vfjv

State Newton's three laws(hkekgrq:0f2 0 +np px.

  Mass and weight

  The acceleration due to gravity is lower onqlo)2d( z/hva the Moon than on Earth. Which of the followinghlo/vqa )(z2d is true about the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a am5ekk6nn -tynw p3//xzsid+e0u4+f distance is

  Who has a greater weight to mass ratio, vd(0g9 g pfg* ,ah)hvaa person weighing 400 N or a person weighing 60 v0 )fgha,p*g (ah9vdg0 N?

  A stone is thrown straight up. At the top of its path, the net force actin7 i3x19 lpcjhmg on it i7pihcx 9j3lm1 s

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same heign*)ohz(/bopa9e4 i mtht. Ignore airo*zao /he)pmnb9 it4 ( resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their98qs81 h ibmfdq lb9e4 respective terminal velocities. Which object experiences the greater force 4el sf1d q9h8 bq89imbof air friction?

  An object of mass m is hanging by a string from the ceilin5 yznw3xd hvem 5cv:/xmt(1 s2g of an elevator. The elevator is mc 2mw n xh535v x1:(etvzmsd/yoving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by d w,w+knsza;.ax;px4p7b v *qd ue)n8 a string from the ceiling of an elevator. The elevator isa8 .vpww7;zea d*+,; pbku xxn)s4dqn moving upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an i1 56 fx nww*,ld3scvxecy sidewalk is

  It's more difficult tocst: 1(xho 2fe9dyv/p start moving a heavy carton from rest than it is to keep pushing it with constant veloc2 1spve (/:tcyhfdo9xity, because

  A horizontal force accelerates a box from rest across a horizo 5s(uc5gmtupd,jkt 24 c*45t cu:m fdnntal surface (friction is present) at a constant rate. The e5tc2c,dspn(5k 4 5m*dtcmtf 4ug juu:xperiment 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 cou fu9 b+;n,a yf;eq1nnnstant velocity. Thus we can ;9n+ n f;auqe ufy,n1bdeduce that

  A block of mass M slides dow)9 a4fskqme6om mhssx+ 87e:fn a frictionless plane inclined at an angle q with the horizon:6ske e87fx ma+ommqhfs)s49 tal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at,r*( ighcsz) mad -v,f an angle q with the horizontal. The normal reaction force exerted by the picv,*fm-ashzr)d (g ,lane on the block is directed

  A block of mass M slides down a frictionless plane inclined at r6y( :s9 fkrcjan angle q with the horizontal. The gravitational force rsj9rk y6(:cf is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously o3- qv jl gf+y 2ujki*wuk+yv- v*j-uq-n an inclined plane that makes an angle 2 -vgj+qq* jwyuu-y k*if k3-vj+l -uvof 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surfa9o4ot xrck:h)e 7(uujce. A 16-N force is applied to the object, and it acceleraut:ek) ox( 4rj9cuoh 7tes 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)/guehjkfl(8+n4y gau,2b k-v 7,kte z6o rde m/s in 7.0 s. What is the average forward for ,r67 +l(/d 2z vk,bahnfkt8k 4jeu-ygo )geeuce on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m1hj o0 u up1uwo(u*jb5/s in 2.0 s. What is the net force acting on the body?5j1owh01 ujo*upb u( u

  An antitank weapon fires a 3.00-kg rocket which acquires a ss rwjmj8 8 9uptaoh6.5+wc5 qcpeed of 50.0 m/s afterjch cws m5qau98j5.p+w86o tr 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 you phcosglr 0kxu3 -7:)mpush a 10-kg mass from rest,ck7mhru3 - )olspg0: x

  What is the mass of a person who wa*ef qbf3rfm7cp/4 w6eighs 110 lb?

  What is the mass of an object that wei,ls8yoe lo3+plp bh -;gmd*z2ghs 250 N on the surface of the Earth where the acceleration due to gravity isyh;o3ps*gbdlop- 8+z,lm le 2 $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass oy*+ze 4yrhys v(jj4*mf the object on the surface h**ev r4j4y+myy(zs jof 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 thvq- b0b(pr g uj /.5ej5yknrqx/4k:dle Moon. The Moon's gravity is one sixth of Earth'4q.0:j/ keq(5 x/u -vn5blkrdpjr bgys. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pz(,+yj zt na9tulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope 9ta(,z nzjyt+accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. n/;n /0d/3 i bffjjebkA force F acts on the stack, and//; bdjj/n ief 3f0nkb 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 48ai hc akl 3-p.;d1l:d. b6m;fm xccl*i0 N stands on a scale in an elevator. What will the scale be reading wh -6km:f bd; 1cipi*ach.x;mall.d 3clen the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rid/ yxxfqn13r 9svj63oges in an elevator. If the mass of the person is 60.0 kg and the elevator accelerates 1onsy3jx/3gr9f 6xqv downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an1xw;sspd,j 9n elevator. If the mass of the person is 60.0 kg and the elevator accelerates upward with an acceljxd;s n9sw, p1eration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. j / m,k 9np+tudg1f1vu5xpec,One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of ,9tvxg e/d 1cmp5j,nu1 f ku+p6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbedm4x79rz4movjluw kde 0u o3(4 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 u r74(4xmmod k w9 3ev4oujz0lminimum stopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests oni y wb5va.35l;e0 qbyf the flatbed of a truck. It is held in place by metal brackets that can exert a maximum ho5y iyfv w3blqbea.5;0rizontal force of 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 y ,wijxr//hqmw5r 85t0j cx*g shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acc5 jj8mx5wi* twq/ rhxg/r c0,yeleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0wj*5 -6hdnle w.40 kg, what is the tension in the string-l5jdwwn *h6e? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a forcjmh.pm tlt4 jkk4y(5mf 9jk. +r6zh6je of 100 N in a direction oy pj4hzk6rfkmk( 95j.mmtt. jlh64j +f $37^{\circ}$ 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 with a force of ;eowvmsj1c9 77oly,*z*vxt a100 N in a direction of 37.0e above the horizov;ctoojew, m*19lyz x a7 7*vsntal. 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 weight 100 N is supported by two ropes as shown l dvkmskrn o)/bmbf /t t8 /7k0;v5d:qin Fig. 4-2. What are the tensions in tqmk) bt ;rbks/ 0t/8/d:f5kvvm d lno7he ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the massezv 0+v z4eu-z of the traffic l0ve v +4-ezuzzight?

  Two boxes of masses m and 2m are in contact with each other on a frictio cebma5zlt/3;7 e*a 7gyt;guqxvx)2p nless surface. (See Fig. 4-3.) What is t lz tq2a*xeam7bgp )ut3cv;/7ge5 ;yx he acceleration of the more massive box?

  Two boxes of masses m and 2m m ytsq37ndd1 gf)+1hnare in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more massive bod7n31fgsd)+1qtmnhy x?

  Two boxes of masses m and 2m are connectfnyg 6h2 o1vh)bhqf3s ;bd67 bed by a rope. (See Fig. 4-4.) If the forward force on the more mao2b;7)h6bhbf 1n s qyv3fh6gdssive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connectedxw-.yi3lbanxs r*f.+eess 7) by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, whf7nissax*).l w3 + exs-by e.rat is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in Fig. 4-5.nk844a3ij hasi. ur3 v Box va3r3u8 in4j shai4.kI 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 bet0;d.kvrj)uturw 2n+et mey9+ ween 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 horizo2dv+;m rtky9.0 ur)+n ej wtuental force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on4 -qrp6 8;iq +wir,lpal7 ftqu wood are 0.50 and 76q;4qwlp,ip rit ru q+f al8-0.40,
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 com7ida cw;xb fj 3t)y0bm++8fines to a stop with a contxm fy+n+)db f3wii 8cb;70j astant 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 pulle v9d5nnlos jw 6 cqpzex:)u/+.d by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of 6ulqd)c.px 9 5e+nnovw/:zjsthe object?

  A horizontal force of 5.0 N accele 0l rb;;p 0.coa21hbbyn6loj wrates 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,ul9n r0cu(/jddo9d6 ;etl:tlc3x emg5 5xnb+ a puck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of ki5b50r+lcx9;tx3 tem6d 9o l cnueju( dgnl:/dnetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skgna vvhh tt1k 5lg6ur*k r/+2lq/9;e bid marks 90.0 m long. They determine the coefficient of friction gql/ervk u*n+hb56a;1 2 /gk tht9rl vbetween 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. (Se/r ttm u7:ub l:v+9vurrt o5o;e 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 out/u:+rv out :r7;to 9 5rlvbmn the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betweew0gu9z g5xqkm.bg.p 9 n the more massive box and the horizontal surface..p09 9ug 5kmqwgbxzg 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 static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is inclined at an*d0f ad-0 *ztw p/c0e ssubht2 angle o-t02/ectzd0h0 usf **as p wbdf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill tha 4-u)d tx8o71rnnax)4pn x ut/qodt;ht 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 inclinn 5 ;jjh ufla4-sec16ix:cp9h ed 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 at,x w*/5emb fmyof5yg0o9ijw:s - jt *k 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 yupsv/7iplt ,4 l6dv6an inclined plane, at a constant velocity of 6.4 / v6tuly,dp7ilpv6s0 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 dow b6a60eh1sft6 (kt qgwau )ez-n 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 k h 4h0brhxdvqbi)-0, 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 f1dyp )2 geh(erough surface. The cable attached to the lo1y ()d2egfephg 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 rou u/nzo6vdam. *-,qmxb m1b :zagh inclined plane tilted at an angle om vm/6xumzqz1o. anb*:, ab-d 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/s7n9i wj hp,2jk*vsh. The angle of incline is gradually inc vpi2n/hjw9skj ,*s7h reased 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 plane?