Which of Newton's laws bq1 8qor+jac5qest explains why motorists should buckle-up?

  When you sit on a chair,hy8 ewq4qyeg7g+xz k jgl,*( 5ku(e+ c the resultant force on you is

  In the absence of an external forcdu(qo19j,r uz e, a moving object will

  When the rocket engines on the starship NO-PAIN- d:jq 7f+p ecwvi;:mq0j0i zdru(4r)mNO-GAIN are suddenly turned off, while traveiid mw jj+0 e)vrr(u:qd:czq4m7f0p;ling in empty space, the starship will

  A rocket moves througk5da k6drkbp4 f;m w( nk50-mf6zvf* jh empty space in a straight line with constant speed. It is far from the gravitational effect of any star or planet. 6(fd4kmwav6 nm jd k;pk f-rfb*z50k5 Under these conditions, the force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and 8a8;3kdcb, xlvy;wl6 xiv 24cwj*qzef8 ous2you suddenly fall forward. You can imply ,oav2vk;;yjde8 4lc868f*2cqbu3 ww liz x x sfrom this that the bus's

  You are standing in a moving bus, fac.ss-. ub i(hbsw/ 0 g.d5qjcgwing forward, and you suddenly fall forward as the bus comes to an immediate stop0i w w(..- b/shugsj .qcgdbs5. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objectt3ua k4tv3uu , ,eg. cn8orde*.

  The acceleration of j yu.ix-o .;1db5 twvpan object is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. 4tn8oveu 1h6) ,ddebdhq9n0xIf the same net force is applied to mass 2m, then th1t8b oe,vxd46 he n)hq9dd0nue acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What acceg7szb4:nq ( ikjtb( s1leration results ibnz7 :s(igbs j(4kt1q f a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release (ydav5cg ;u/8sls mp9it, the balloon will fly away. This is an illustrdsy lsp(c5avg8/u 9; mation of

  Two cars collide head-on. At every m*f:qbc02recwr nk3 j 0oment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force the second car exerts on the first. This qc:f0c2e jrkn0*r3 bwis an example of

  If you exert a force F on an object, tbom/l/mjj l w/*j84fyt4 e c*phe force which the object exerts on you willemm4 l j4/bop*j*fwy/c/ jl t8

  Action-reaction force+smspm b3p/d . sr*7bis

  Action-reaction forcekb-9v0 ;tqd4 sibr7wks are

  A 20-ton truck collides with a 1500-lb car and q6w29y -z y bmiw(e5evcauses a lot of damage to the car. Since a lot 5 e(w yieqby-v9m 6z2wof damage is done on the car

  An object of mass m sits on a flat table. The Earth utv/0j0pu6 bm pulls on this object with force mg, which we will call the action force. What is the reaction force/ju u0mb6 0vpt?

  A child's toy is suspended from the ceiling by mea:-isu0 fa)u rens of a string. The Earth pulls downward on the toy with its weight fse)uur f-0ia :orce 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 1og d*pzi6fgu04ab )y1 500-N instantaneous force. The ball hits 0gfiopd )6*4uyazgb1 the bat with an instantaneous force, whose magnitude is

State Newton's three fk: 59qy6motvhy/s k)laws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon thanty2ik6cz x-*9q(1 rxvs xa) ee on Earth. Which of the following is true about the maycixzx* qtak-e)(vx2 9s er16ss and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force whicxt iz7w9c rxod/7(h: o*qma g)77j6l kwtk.kp h acts at a distance is

  Who has a greater weight to mass ratio, a perme:g7(f jeofw( ) ps+rson weighing 400 N or a person weighf) g (p(7ermewsjo:f+ ing 600 N?

  A stone is thrown straight up. At the top of its path, thn1e zu ;,pxh(xe net force acting on it iexzn1x; , (phus

  A 20-N weight and a 5.0-N weight are droppedz6cb x v,-zcql-zh*(s simultaneously from the same height. Ignore6*zl -vs-(bcx cqzzh, air resistance. Compare their accelerations.

  A brick and a feather fall to the earth r; ;ngew+,vhgat their respective terminal velocities. Which object experien,ev;rnwh+; g gces the greater force of air friction?

  An object of mass m is hanging by a string from the p:t hb2 ,kb)1fy8.iaxscqbd)v;2wv q ceiling of an elevator. The elevator is moving up at constant speed. What is the tension w i :)bc abb ,xytdq21vqv.8 ;ksp)fh2in the string?

  An object of mass m is hanging by a string from the y+ c;:5iewcviceiling of an elevator. The elevator is moving upward, but slowing down. What :i +wccye5vi;is the tension in the string?

  The force that keeps you from sliding on 0w)3l b +esnoyz9/jetan icy sidewalk is

  It's more difficult to start moving atq1lmu0ek4gl /k17 d n heavy carton from rest than it is to keep pushing it wi0n/11l7kd4mgqe ktulth constant velocity, because

  A horizontal force accelerates s. 3xqzqdmg0g9 pir+9a box from rest across 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 force is doubled. What happ0+9g9d zixsqpm grq .3ens to the box's acceleration?

  A packing crate slides down an inclined ramp at consnw7q6ix go)u8 ah2 *zztant velocity. Thus we can deduce thzw* x7nu2q8aoz6i )ghat

  A block of mass M slides down a frictionless plane inclined at an::cq+x kx hxiee-6ss4 angle q with the horizontal. The normal reactio4e+h: -ssex qk:6 xcxin force exerted by the plane on the block is

  A block of mass M slides down a frictionless 8iziys u6x9zh, 4jqy5plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plan uh8zy i,5zxsqi6 9j4ye on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q witctl io)t y7,1th th) o71i,tyl ctte horizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneo0n -qyr ewdv.(ax (:tmusly on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after be. dmtrw(ea0 :-n vy(xqing released.

  An object sits on a frictv9,pdd t3 ciq6ionless surface. A 16-N force is applied to the object, and it acceleravp qi tdcd9,36tes 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 27bxkbz*)vm2 q z4t cw -)1w5uqw m/s in 7.0 s. What is the averw )bcwqq)z mtkw*2-uvx4b1z5 age forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. n3 -amxkbu59+0q zvci What is the net force acting on the bodyv 9-zink3cbmx+5 0uq a?

  An antitank weapon fires a 3.00-kg rocket which 04-.kuvn+c8mw//x3tywsu rw* o26ef ryc fsoacquires a speed of 50.0 m/s after trav3ek rnx.srso yo0c +4 utcwm /fv2w*-y u6/fw8eling
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 froksc q+ 8j*n5x99cb*cw8svhvw m res8 jn9cb9+v 8*cwsk x5qchwv* st,

  What is the mass of a person who wei8a fm p+e ayzetz6m5e:,qke l2)od4h0ghs 110 lb?

  What is the mass of 50(x7qi9v fb lg2aiotz 5wiy,an object that weighs 250 N on the surface of the Earth where the accelera09f55a2zw y xt,i qii(g7lbovtion due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What +q0; e m3jlkvxis the mass of the object on the surface of the Moon where the acceleration due to gravim;xq+e3v kj0l ty is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B d d;qv9iy-wuo5)qum*5j2eoma,1 qq q weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of u2ju*, ;d 19)q weq-5qmvom5ad yqoiqthe objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends ofb8at+w gmp.bgi:8 3/ cgz,/drfayh u8 a 5.0-kg rope. S8g/f:db rzy ip/mw+,a8h gc bt3.gau 8ue pulls with 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. A force F acts onw2cw xt*z33zu8h)meo the stack, and it a)2h3z8mw uz oc3*et wxccelerates 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 48d z)z.2* iumgo0 N stands on a scale in an elevator. What will the scale be reading when the elevator is o2zm)diugz*. accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an8 72 w:idvnnrf elevator. If the mass of the person is 60.0 kg and thedfw2 rnin 87v: elevator 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 mass of the person is 60., k*aq+k,pi9yj/c 0z n c rlwag3jk1h70 kg and the elevatorr7c*1 w/,0ljnh,9+ziayq ckp j kga3k 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 purpkvgoz9u5 4n+p( .of 8.0 N and is directed due north. The second force t( pp4uvr9. 5u+p gonzkoward 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:rqe 0pf e5s1+lg ynz6. 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 theg 0se qeyn:+l5r61fpz minimum stopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on *mvzu :(c 0dvtthe 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 traveling 15 m/s, what is the c :v*0td(mv uzminimum 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 apcv;-tgv) uwtf mt9+5nd m = 0.40 kg, what is the magnitude of the acceleration of the system? (Igm9v;tv )+c f5t-gwtup nore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig,pt3l ng2;/n: dnidy f. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tei ng;pdn,yd: l3 t/n2fnsion in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizoy9qmpkkcbe 8 ))u.eel.9xd,doq /ln( ntal floor with a force of 100 N in a direoquc9. dqy)8 )dlbm.( e/ nplkk9xee,ction 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 horizo:mq-n x8/sn rmntal 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, whaq/ 8r-msm:xn nt is the normal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown in F.qd bn dvt. .:j*z v:a8;zkaasig. 4-2. vtqd.k:b za;:j8.*szdn.a a vWhat are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of the tr3ryqfkb3tb -x mwi8.w-7,ksz affic ligb- .wzk3b7 wk8rmtx-y is,f3qht?

  Two boxes of masses m and 2m are in contact with each other on a friction3ht058r-su zrx0 jep6vm 0kroless surface. (See Fig. 4-3.) What is the accelerjmkxr0 0p ze80o 3r6rs-5v thuation of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionlesh52a9vxo /0 me(zwwfis surface. (See Fig. 4-3.) Wwavx eow9mz 5i/0(2 hfhat is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. ecy(1iu 5xdbd3.3mfa/fg kx 4(See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the connex3./ mcby1fgka4 (xd d3ue5 ficting rope?

  Two boxes of masses m and 2m are connectew2; +xe ve*svr 8g2fifd by a rope. (See Fig. 4-4.) If the forward fors8gfv2 f2e exi;vw+*rce on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley eel,y+*d etu0-r)(v9(bpubdvte + zias shown in Fig. 4-5. Box I ov*0,e)v et rue (pldbbutdzi++(9- yef 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 l ik5jujd gvi7b+.ah:+xe75 fkinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectivelguh.x75 + k:dvlj7j+abeif5i y. 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*gt. h8r lqyg.ictions for plastic on wood are 0.50 and..*yl8qr gt hg 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 i::en x3 0st:50bf 7av6o ihq7//ja omtb etpfhn the +x direction. It slows and comes to a stop wit6ao:t b: j3f0 5vn/h/thsmfqboatp0ex7i 7e :h a 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 surfaceo;jgy8 ml9y qi d4i,-l is pulled by a 5.0-N force. A 3.0-N friction force retards t- li;ym ,8d9jqoig4l yhe motion. What is the acceleration of the object?

  A horizontal force of 5.0 N acruwnz t/ fzeo11zyt65p)4 um.9gls) zcelerates 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 pu*-qqkr ( cuk;nax *8bnck is given an initial speed of 10 m/s. It slides 50 m on the ice befok r8k(-qau*x*c ; qnbnre it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks 90.0 m+ 72lsgg/60lpiwoh 98 tzfopn long. They dete2hn7 i6p0tlo o lz+fg9ps/g w8rmine the coefficient of friction between 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 arl+m*p t g7vp s7)4ytlxe 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 slide on the more massive box, what is the static friction force opmtx) p7+4ly lt*g7vsn the less massive box?

  Two boxes of masses m and 3m are stac 1eifgm4 vdn6 q+p/a3jked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is a/j6f pmn3e+i4qdvg 1smooth 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 in:ep9o10vufbl clined at an anglee1o v :b0pfl9u of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle of 8i qnk cycxdb((;8e,5l6a3y k me *wpi$10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclined plane wi(ql vegxg +0k7th 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 i ,i0g32bwu q azc3u1venclined plane tilted 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 down an ih2rndzir**i2fm v+)or z4zz gom50 r,nclined plane, at a constant velocity of 6.0 0z5+om) f v4dz2ho,mz rrirr *2nz*gim/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./kuoxdm:ivuw1co7o-l63yx 1 xta )3(aaqe b 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 drn0o) ohy g1i);lzqqa)uj n,5 own 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 wko*d3f g4 8n 3hw3t2melj.orfeighing 500 N along a rough surface. The cable attached to the lhdfjf. 3g ke4 l3mr2ot8o *nw3og 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 rough inclined plane tilted at an ogdr.cg.rf)vk. by, + angle of .o+.drk cgr. ,gbv)yf $33.5^{\circ}$ 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 incl5oqe8d ma2*s pine is gradually increapm*o2e5ds aq8 sed 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?