Which of Newton's laws best explains why motorists s32:g -.o wsut4usigc-jw3 ilwhould buckle-up?

  When you sit on a chair, the resultant foro)a4v hy 2(bf45vh g+ lidc8zzce on you is

  In the absence of an external force, a movingj(p9ijj:2al fqw9h b/(0 nag c object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddfr( a6vq/5v(y lp4vxmz a 21gdenly turned off, while traveling in empty space, tflv4pmz51 vav(y gd/qr6x( 2ahe starship will

  A rocket moves through empty space in a straight linem3h l2; jc/tc78pn cmz 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 rockcl/ cm 7hc2n;m38 pjtzet in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddenl99u 2zt cx/pyak;gb4b1ns 0gwy fall forward. You can i c/szxu4pty abkw91n gg;290bmply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenbjyl++3hzf 7q42 zik /q53gpg h hk*pxly fall forward as the bus comes to an immediate stop. What force caused yfhigqy p 7*h52b3k kp ++z34xlzj/hqg ou to fall forward?

  A constant net force acts on an object. Describe the motion of the obj-h t0a vmkywrcn;c*i-db,7- p75ers bect.

  The acceleration of an object is qn*vmk3. 9o,ac cik;linversely proportional to

  A net force F accelerates a mass m with an accelyvvpb4/j;s +v, ajfo :4siep 3eration a. If the same net force is applied to mass 2m, then the acceleration wpi+4, fjbs yeo vp3/av;:j4svill be

  A net force F acts on a mass m and produces an acceleration a. What acceleratih3,)(+ kuub g cmy*dr 9vi8zlron results if a net force 2F ac zchgb*i )mr3uy+ku,rd (89 vlts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly awaylko8p:hqmm. 2. This is an illustrakml:op 8h .2qmtion of

  Two cars collide head-on. At evlkcvm(.2q ut 0dd7d-qnnq/ 3qery moment during the collision, the magnitude of the force the first car exerts on qdv0(-d2ndqlqmq / n3uc7 .kt 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 object exerts on youj se: tan w*7sac *7cw-z.b)xj wi b7zs w-t*c j :waxna*e.csj)7ll

  Action-reaction forcyg) mnr.7r hwn 90ng9x+xilm3es

  Action-reaction force z2ca4yucr-b 6s are

  A 20-ton truck collides with a 1500-lb car and causes a l60sped2u (g pdot of damage to the car. Since a lot of damage isegds0p p6 u2d( done on the car

  An object of mass m sits on a flat table. The10tgn1whv,)jlb f r 4d5smp0w+vp3il Earth pulls on this object with force mvj p,nih34l tw5v0b1f )+s wmg p1ldr0g, which we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means huh )zif)02xhimlq/ *of a string. The Earth pulls downward on the toy with its weight fohu* 0f)2lhiq x)mz/i hrce 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 1 pxtxn,9pk );4ap69m n v6dvz lmelx);500-N instantaneous force. The ball hits the bat withn)d)9lzm;4k le ;vnvx9m xpx,66p t ap an instantaneous force, whose magnitude is

State Newton's three laws.n k6fr4dheh; qegn;avym s; 8* h8:zs7

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Whp40 qc .qubaqjs8ov z3 zm6:q8ich of the following is true about the mass and weight of an astronaut on the Moon's surfac uqqj mozz80.qbv4:6s ap8 3qce, compared to Earth?

  An example of a force which acts at a distance g 3fgd4i v ;r0hs7*dsfv,z p0f7q+njw is

  Who has a greater weight to mass ratio, a person weighing 400 u/ dk/sull3kd-k c02 8vd-jdf, .oplkN or a person weig k/k8lufvdljldkds,/3u cdo. 0p-2k-hing 600 N?

  A stone is thrown straight up. At the top of its pa0m7 jg)o q)zc5c(fgn,fol ; qath, the net force acting on itcj)faof g(o0c;7l,gqm5qnz ) is

  A 20-N weight and a 5.0-N weight are dropped q- qf*nwx-3lx:ik e s+7:cismsimultaneously from the same height. Ignore air resistance. Compare their acceleratqii nmssk+xwxe-f* 3 qc::-l7ions.

  A brick and a feather fall to the earth alvc;mo ng9:7i17fis+d/.cua 8qvum et their respective terminal velocities. Which object l;id9 8.7 gc sucq/7am1+vvo: nmfeu iexperiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. oovy4 a,(f6m z-t+wjuw4k3c fThe elevator is moving up at constant speed. What is the tension in the string?z+-w j3mt4o wv o6ky(ucf, af4

  An object of mass m is hanging by a string from thewh*7yeg 6t;j; esio n9 ceiling of an elevator. The elevator is moving upward, but e 9sytoh 7w;gn;*ij6eslowing down. What is the tension in the string?

  The force that keeps you from sliding on an iqu2+d3po5 3v xczfy-icy sidewalk is

  It's more difficult to start moving a heavy carton f2yumin :*t4fo rom rest than it is to keep pushing it with conf4*:ym ut i2onstant velocity, because

  A horizontal force accelerates a box from rest -l) :tl e8ys9 anuaa)uacross a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal fo9lua a8nl-: su)) yeatrce is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined rr,)e7 zsb(k )p zx(mxv/za/ vcamp at constant velocity. Thus we can dedcvxr /a(es,vpz /xzb(z7k) )muce that

  A block of mass M slides down a frictionless pc:u3ag nkxopt7h08f:b idk*/lane inclined at an angle q with the houd /cto37k*::b kg8i0fh xpnarizontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at bjb f8.0k9ufl an angle q with the horizontal. The norf 8buf9kbl.j0 mal reaction force exerted by the plane on the block is directed

  A block of mass M slides lbqs 2+xkmvy48 dlejws 7niogn(- 24+down a frictionless plane inclined at an angle q with the horizol nsixsgwynk4+(m e8 obj2l q d7+4-v2ntal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultmwg)jk 5x 8d a+7p1 ah0z(iqxxaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being5+7hjgqi xk0(apzadwm )1 xx8 released.

  An object sits on a frictionless surface. A 16-N force is applied to the8gt8b mafmh:* object, a8 t f:aghm*8bmnd it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest1,+ebvnf l5f dbg0 l-n to 27 m/s in 7.0 s. What isf n1 l nd,g0vfbb-+5le the average forward force on the car?

  Starting from rest, a 4.0-kg body reach fq4qzsoss1 i u+pk613evti9;es a speed of 8.0 m/s in 2.0 s. What is the net force acting on the +tsqf1; i3e1k ips s4v oz69uqbody?

  An antitank weapon fires a 3.e8cu.vf zqo6t(x:ij8 7zed)j00-kg rocket which acquires a speed of 50.0 m/s after.oq j7it z(d8)xe6:zjvfcu e 8 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 push a 10-kg mass from ryu1* +c yui1/az:rwwl6( jqirest,6+q1*rwzjyiuliyw(c u:/ a 1r

  What is the mass of a person who weighs 110 lb? -e yup;d/ 0lqewwa9p9

  What is the mass of an objecth p.;+yqbtk::kl yc.o that weighs 250 N on the surface of the Earth where the acceleration due to gravitytl.yp: :.bc;+oqkykh is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the ma9jzwv71w ky o9ky1h3)pdphk9 ss of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of that kd99kohp py wyhv1739j1zw)kon the Earth?

  Object A weighs 40 N on Earth, and object B weigh4gnvied2 1w *ps 40 N on the Moon. The Moon's gra 2p i4w*ed1gvnvity is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling onxo. ;b mgvxq0,:fl3yejt7pc: opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is moj:fx p,xq 0ltcey;g37vb: . 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. A force F ad/vdyp knl/nyu gb+9 5kfq.63cts on the stack, and it accn//96k.yy+b vlqdpgnfd3 5uk elerates 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 elevat )o7 l.-gd7p9m/svab;l njc be4r epw(or. What will the scale be reading when the elevator is ab(w- 4lm;dvg97 la.n7 j/r sopbcee)pccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the maura dx 6yh 5:9xd1atd ow3:c,sffo32fss of the person is 60.0 kg and the elevator accelerates dtdwsa1o3f5h o 9u6f:,2d3cfxx:da y r ownward 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. Ik xpv r+cj).j 8tokc5jhb;8i4+i7yf vf the mass of the person is 60.0 kg and the elevator accelerates upward with an a +pb)iv4tc58oj8 xj f+kyc;h r7 .kjivcceleration 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 ma w(wiwa4u 32tm.-ucg. m.eew egnitude 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 accamwe i-w meutwc2e3w.. u.(4geleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is he +0ueul9:teo4e.x1a ayk1u zf ld 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 distance if the load is not to slide forward into the cab?o 01.yaauf9ute1 4xke zu +e:l

  An object of mass 6000 kg 3u,t:mb* wdhfh3srz 3rests on the flatbed of a truck. It is held in place by metal br hwfd,bus 3h 3mt*z:3rackets 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 slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.jy78 kdwgzz,;xn5jrta-fu j-,ff- w : 60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the j 8tn,gazk; -5f-w7jduxy ,jwz-:rff mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, ii -,l; td5d7 c3c1zbw t4ffqssf M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Igctt415bd - ss;zc3l ,wif7qfdnore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor wt 0g0/u carxz gap/ )clw73at)ith a force of 100 N in a direction of 3 ta rpzag)t07l//)ucca0gxw $37^{\circ}$ 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 witrned 2dr id::io+x g- jj)5pr7h a force of 100 N in a direction of 37.0e above the horizontal. If the mass or7)p:r5jde+dr inx -gjd io:2f 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 suppor,j0)4q,b ; ubma0kk ozl iomgus4i9:oted by two ropes as shown in Fig. 4-2. What are the tensions in k0oui9jk: zqb ;m4,4gols ,)moi0ub a the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the fxu 5. i7ube2qmass of the traffic light?5q b7. iuxef2u

  Two boxes of masses m and 2m are in contact with each otx2t zr4q :k oo4n mb::jw*u4qlher on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more m:woxqbl2r :uz o*tj44:q k4 nmassive box?

  Two boxes of masses m and 2m are in cocac.47rw :wtontact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more maac t 4.cr:ow7wssive box?

  Two boxes of masses m and 2m are connected by a ro)ej ,1z0ez8zdbzd ;m spe. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tenssdbez8)zdjz ,;e 0zm1ion in the connecting rope?

  Two boxes of masses m and 2m are connected by a rog- 7wym8r2pvof0 rpi4 m;a gk(pe. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massiveamfg 0y8(irr-p pk;wov4m7g2 box?

Two boxes are connected by a cord running over a pulley as shown in Fig. 41cy 4w g: (m ;wxiyrvjoox nz(tpc8.80-5. Box I of ma8 ow. jvzy w (t1rpo08mci4x(xy:ncg;ss
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 kin / gyzeyd77,hdm5iy;n etic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respecti7yymd, 7h/5i n;zgey dvely. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic fr,ojf 1jbqro 9 jom770kictions for plastic on wood are 0.50 and jo 7jko 0bj,o7m9q rf10.40,
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 to)nci4bt p6d a6h9c3t9rm kec o-4p9mt a stop with a constant accelerat96iec)t9ord tkmanbmhp44p9c6 -3tc 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 suv7ozyfov*d(l6 tf 2w 7 nymd+4rface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. Whatd6nz*yvl74 y+7of o2mt(fvw d is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass,k4-x+ims18u c4r/hfz*uu o 8fnk vo/v 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,y,vr-li rr 1s 50 m on the ice y-,lsvrr , ri1before it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffsgex gw-e. hzn9w 4o)-ic accident, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and twn9--w e4zox)gesh. ghe 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.) Ts)u pn/2ytr3 p , rrs3*izqpuu+u8uc5 he 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 th*c258,rprqsy n+spuu iuur p 3t /u)3ze more massive box, what is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. jh6yx) v, p: bu.w hzpr.wn5dug7 z*y. (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 lessxpyud.bzyr v5 * p .jgznhwwh,67.:)u 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 o 2/znljpj.l 7inclined at an angl2.olpz7l/n jj e of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that cd l2hjdnv5)m+ypo; n;9r:o nmakes 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 angle of,dduw vai t,ja:*w( )l $37^{\circ}$ 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 9 ab,g 8;e+uke. kl ozilwm03uat 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 df-v+/s5tr m xtirectly down an inclined plane, at a constant velocity of 6s-v tmf/rt x5+.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 a1)+ w.jdojsdjh sr;p:u /lsw 1 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 downjh*,dirq bq dtzde(g6*( yi/el il. :- 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 slkw1f 8qof7cvw9 d2(asj+p-x; k3;qzl- vplattached top1f q9( 2vd pow83z-s;7avk-+xcsw qklf;ll j the log 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 fr ;6cxe8d s6wvfjaxuj5*. ,l+v: i aatvom rest on a rough inclined plane tilted at an angle of v6,lf w v j5aadvsxx6eic;.j+:*8 a tu$33.5^{\circ}$ 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 ;p3 n;ih*he,j uo; vrzof incline is gradually increased until the object begins to slide. The angle at whicpoizjv,hrh n u3 *;e;;h this occurs is q. What is the coefficient of static friction between the object and the plane?