Which of Newton's laws best explains whh9:v1 +auzjy wn sv;f2y motorists should buckle-up?

  When you sit on a chair, the resultantl6ft5iya;2 ehw o0ucv 6h7j r8 force on you is

  In the absence of an external force, a movin1vyaotd5;ovqjg 0 b./ xf /a,es.il(dg object will

  When the rocket engioct; x pt*k9) unuaf7/5or-kmnes on the starship NO-PAIN-NO-GAIN are suddenly turned off, while kmu* 5;po7xta -k roucn9/tf )traveling in empty space, the starship will

  A rocket moves through empty space in a st clbn rq*n9d.a ;t:n))enh-7hsa f2z rraight 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 sustainbz)sehr;nnnn .h72 tfqacd)*: al- r 9 its motion is

  You are standing in a mobc+/+uioqz k q 8g.2dzving bus, facing forward, and you suddenly fall forward. You can imply from this thqozc k iz+2b+ q./dgu8at the bus's

  You are standing in a moqve eu (j0ua+: *(,asjs8mwwsving bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stsej,sm qwuv(s(+0a8 e: *uwajop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objecf86 g:iw)iyewt.

  The acceleration of an obje 1 1vdis,bxs,uct is inversely proportional to

  A net force F accelerates a mass m wim g0+ g.m0 lwx,v*wlsli 1foi-th an acceleration a. If the same net force is applied to mass 2m, then the acceg+s*w 0m1 l.w,miglvix0-fo lleration will be

  A net force F acts on a mass m and produces an acceleration a. What ac/wguta: a4e ,mceleration et:w4m/a g au,results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon willos6n .7djnl 2u fly away. This is an illustration ou26 dsolnn.7j f

  Two cars collide head-on. At every mdfp6jk:yrf+xl-y5 3br;p s.d oment during the collision, the magnitude of the force the first car exed+pl63 f: kr5py-xrfj s ;dy.brts 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 object, gtot;i6ttl+qega,03tk pp:3the force which the object exerts on you will tp e3;g oklqt3p+i6t:, g0tat

  Action-reaction force3 g:zp0n xvnf,3 yok7hs

  Action-reaction forc .5e hg1vpkfd/es are

  A 20-ton truck collidesg g*,bk6w*yq(kfvjn 5 with a 1500-lb car and causes a lot of damage to the car. Since a lot ofj6g*n5yqv *kfb,wk (g damage is done on the car

  An object of mass m sits on a flat tabt13rguw7* q vc.fv0kyle. The Earth pulls on this object with force mg, which we will call the action force. rqyf7 wk*3vc01gt u v.What is the reaction force?

  A child's toy is suspended from the ceilinblk cdf,(yez2 91kr b h,5fq6ng by means of a string. The Earth pulls downward z k2dqe6bnc( fhkr 1b,5,y9lf 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 a 1500-N instantaneous force. hisj3kd jg cp+9 n./m0The ball hits the bat with an instantaneous force, whose magnitude cjj ./039gnsk hm+dipis

State Newton's three ).)m ukqzq/ee - 1 ujyhu*edmg83.fw rlaws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon)rto a4uwud0u9.4chi* ws 6v r than on Earth. Which of the followingcu.09*4r s4o urvud ih)wwta6 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 sg i*u3(8(qqkj:rs hd at a distance is

  Who has a greater weight to mass ratio, a perw02dd*,dzum4wif6e;et bz* + zngn w +son weighing 400 N or a person weighing 600 N?d;mi z b*e2 n u*dtgfw6e ,dz0wz++w4n

  A stone is thrown straight up. At the top of its path, the net force actizgq 0e9f .mqp.ng on it zmf.e. qgpq90 is

  A 20-N weight and a 5.0-N weight are dropped simultane9i2wnc8p 9 x7oj*l0oehb lmw*5w/ cvuously from the same height. Ignore air rv9i / 0oobuc28cwxw5j7hw*9lpm n *elesistance. Compare their accelerations.

  A brick and a feather fall to t9idt jh.:3vk7kvn r6uxui-p2 he earth at their respective terminal velocities. Which object experiences the greater force of air 9ivuvp2n-t dikkuj7:.3 h 6rxfriction?

  An object of mass m is hanging by a string from the ceiling of an elem x-*gedz7*l cvator. The elevator is moving up at constant speed. *-*mz7ldecxg What is the tension in the string?

  An object of mass m is kbr(wymw eapjx.pvmh .06 (+;p .f;dzhanging by a string from the ceiling of an elevator. The elevator is moving upward, but slowing down. What i6 ymafz0e m.k.v( ;brdhwp+pp w.x( j;s the tension in the string?

  The force that keeps you from sliding-kjpz3y -2vbtts+ zb, on an icy sidewalk is

  It's more difficult to sh5u/1evbyc6e,9 5 v nmc: 80vzmfte rjtart moving a heavy carton from rest than it is to keep pushing i5 5nh8vbemy/0evc:rzc m91t6u v, jef t with constant velocity, because

  A horizontal force accelerates a b,s5lf.r plktbb ( d7c9zu, kd3ox from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remat dzr l7b3pks,bk 5(dfu9 c,.lin 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 io p s +3vyml-5i.do:xconstant velocity. Thus we can d.x 5m: -yp3i+lovdoiseduce that

  A block of mass M slides down a frki,l(yer.u q,0jek5zd 33 /h vpy7kqiictionless plane inclined at an angle q with the horizontal. The normaqeiq y 5y l03j3e,k7dr/zp (i,h.ku vkl reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angle q rg 69)3lby/ji-e vozg with the horizontal. The normal reaction force egz )/ v gyebo6j3ir-l9xerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclibw7z8b(b pdo(+l va*eh-:huwned at an angle q with the horizontal. The gravitatiovd-h*w (eu 8( :b+hwz7 ablpbonal force is directed

  Two toy cars (16 kg and 2.0 khq e e0gqpxqai7 509rc38e dr3g) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being re gci9x qa ehr0pee5d37q 0rq38leased.

  An object sits on a frictionless surface. A 16-Ni2 i7f-llu*q v force is applied to the object, and it accelerq *lui i2fl-v7ates 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 7.0 s. W,ci(m4 tw m:cshat is the average forward force imct(w4,m :cs on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. m hhz ms)k6p;e)wjq3/ What is the net fo/ ;6mhh 3j)ws q)zmpekrce acting on the body?

  An antitank weapon fires a 3.00-kg rock5 icj ys c+bj,-y21garet which acquires a speed of 50.0 m/s aftebjri -5c1s+2yyg,jc a r 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 h n ./ ;.ks99vt2 j;xv.nzoiaseu m+rtthat you push a 10-kg mass from res; hrnn;s.k.9 v 2./+a9eoi utxtjvmzst,

  What is the mass of a ps3 ddjs5s x6o* hp/dosapm.w mias6+*gh72 5v erson who weighs 110 lb?

  What is the mass of an object that weighs 2 t; up nh4;sapcvt 2d,snzd p1/3q6.ze50 N on the surface of the Earth where the acc4zst.hpq6e n2/a3tsz;u1n, dp d;c vpeleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass:xnktfv82 9 bs of the object on the surface of the Moonk f9n8x:tbs v2 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+bmary;:i fth( dst f;i)9bg3 the Moon. The Moon's gravity is one sixth of Earth'atim;g:;b)fhy9t( i3d +r bfs s. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling ;9un 9a symig:y40sny on opposite ends of a 5.0-kg rope. Sue pulls with m9y9yin :n4;0gy ussa a 15-N 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. rs 2xv4,pc.cn9 6fobq A force F acts on the stack, and it accelerates a4 x p ornf6sb2cv.qc9,t $3.0 \; m/s^2$. 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 an5xfmr(v;gpl e++ 3/+ebowqxw elevator. What will the scale be reading beq;l(+foxxw p3g+vr+ emw5/ when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the ml-v(;ve y32 pawhbe 4f p*rs)oass of the person is 60.0 kg and the elevator accelerates downward with an accelerat;v-(2vo*hypab 3p)r sef4 lewion of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If the mafcw p.f,5.l,m3 dlxzd ss of the person is 60.0 kg and the elevator afzwldm5.3,l ,xp.cdfccelerates 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 forcw f7vy-p xup;-e has a magnitude of 8.0 N and is directed due norupx;-7y -pv fwth. The second force toward 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 dc naaxhpk.02z u9 r(t6sj*)v of a truck. It is held in place by metal brackets that .tj(2dkp xrsu9*vazan h06c) 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 flatbe79) sb)j6)i fggfsmyxd of a truck. It is held in place by metal brackets that 6fjxsmg9b)sf i g)y)7can 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 slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.4,qwhheqim4 965 pseg,0 kg, what is the magnitude of the acceleration of the system? (Ignore fri qg4pm9h,esih,56eq w ction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = r(1g fvf-h p(l0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pull fgr v-(f(ph1ley.)

  A student pulls a box of books on a smooth horizx7 q(5a0pz:9ss(z gqa 3 neigvontal floor with a force of 100 N in a dir5vqa(qx3gi:nz sz9(ep ga0s7ection 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 boz98h ufke84wuth,d1u x3 a6 ecy8l.w4qn4cqe x of books 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, w8fn49qz6uwh8wu. 3u4e14c ek a8ec ql,xdhty hat is the normal force on the box?

  A traffic light of weight 100 N is supported byo /d;8zd +jgo.ric1dy bqs5 8e two ropes as shown in Fig. 4-2. What are the tensions in the r irsy+od81dz; e cb/d.g8qo5jopes?

  In Fig. 4-2, if the tensions in the ropes arui7/.c 9 k/oowh1* mzxhdxd6zqox *2ae 50 N, what is the mass of the traff/x* xwo zmxh ozc1976ahduk*2d/qi .oic light?

  Two boxes of masses m and 2m are in contact with each other on a fricjxdmete*s ; bgc(,p 71tionless surface. (See Fig. 4-3.) What is the acceleration of the morp1xect,(edb*j gms; 7e massive box?

  Two boxes of masses m and 4avzrka9, ay72m are in contact with each other on a frictionless surface rava7,ya4 kz9. (See Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connecteg8prq)h ):8zb bu ,srhd by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the connecting )b h,ugzbrs) p88:rqh rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If thlyxh:m5+m sp, 7vu(i8 6v9:tmtctqqp e forward force 6m8v y5(lpchmuiv ps7tx: q+tt:9 mq,on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected b ma z0qja-l1e9rrg 3.dze8 6lky a cord running over a pulley as shown in Fig. 4-5. Box I of ezl8a1k g0j3erl .-m 9r6qdzamass
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 3.0-kg box anc-. 7jq0lfz,t p . c)xi/gvoxed a desk are 0.40 and 0.30, respectively. What is the net force on the box wh c./ iv e0pgo.7,xfqxztl-)j cen a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions foc0c y. ;+nyw aq :eea*1aotbw)*k: uefr plastic on wood are 0.50 and 0 ab1**) +kye0eca: ;to.awwye qcfn:u.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 surfawwdgi- *dpoo (-fy tw(xgzgu7:2du4 1 ce in the +x direction. It slows and comes to a stop with a constant acceleratd1:iw4oxwfu dgzu gg d -w2o 7pt(*(y-ion 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 59dn vfd l.sd32.0-N force. A 3.0-N friction force retards the motion. What is t3nv.f2d l d9dshe acceleration of the object?

  A horizontal force of 5.0 N acceler c j;+*13dtgjqn:tb yvates 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 p,uwz5zs47og dx8(*g 4bnd9;yx, oa4 zejvj l muck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck,z v;, u4jz jx87gwamol9ge d*(d5osb z44xny and the ice?

  During the investigation of a traffic accident, police find skid marks 900+ha9kxhi :sq e(a 7op.0 m long. They determine the coefficient of friction between0qioph(ae+ 7sa: kx h9 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 andxdr4p(kt s7t)n 2) aitxpb r1( 3m are stacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surfac(s42) a7rtr pd1px ntt(k)xb ie 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 less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface bety o4f2n2 2qvjzyo5 -bc6 1stobween the more massive box and the horizontal surface is smooth and the surface be15jo22sotz -b c4y f yvo6b2qntween 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 pl7b gpivc397.vtsx s: eane. The plane is inclined at an angle s.ps :tb9 cegxv3v77i of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an ag*,di; .)tyxb 0dvqsungle 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 angl2(wn 37,i-bx vnczd )scazl)ie 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 atnn: o4 5moya+p 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 inclinedlclu6mtc 8s 2pg 37l+r plane, at a constant velocity of 6+ltc ml6 2l3 ugsr87pc.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 rough uqn2q0xn3.ota2onyj3 ..gtj $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m sau77*u0;egoj9ce kwecae7 ; xlides 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 cable att2i i:h.wsjfadbe4zk* y62 ax 3ached to the log makes aa:3fhkixzbj s6a 2e*2d y.4w in 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 inclj ,1n,m-ndup4aiu )f c5yt 0vzy,ve l.ined plane tilted at an angle of,fndn01cmz,avut 5 ylup,vej 4 )-i.y $33.5^{\circ}$ 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 gb ;ymm3 n:sk9npewne/t4 +/ab) 0tt furadually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficientwateb):nyb4k ts93 p/n+t e0n;/m mf u of static friction between the object and the plane?