Which of Newton's laws best explains why motorists sh(e;1 (u9 kya yc7rf4xx/)iuraanm8rwould buckle-up?

  When you sit on a chair, the resultant force on yout.9 dvn8xtc ,c is

  In the absence of an external force, a t gg.fhbb(6 :y04u bavmoving object will

  When the rocket engines on th):opv sz mi. 45yjd*oae starship NO-PAIN-NO-GAIN are suddenly turned off, while travelinidj .s)amo5pzo*4y:v g in empty space, the starship will

  A rocket moves through empty space in a straight line with c y,n7 .lo:i qa7pz8bcronstant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the cb8 7q:nyazlr.7p ,oirocket in order to sustain its motion is

  You are standing in u6ss8vxzfl*+ a moving bus, facing forward, and you suddenly fall forward. You cs +sfvx8l 6*zuan imply from this that the bus's

  You are standing in a v 3qsts;d +n8v stij34moving bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused yoisjstv+8334s; qvt nd u to fall forward?

  A constant net force acts on an object. Des3 9x.yeh etk-ycribe the motion of the object.

  The acceleration of an object is(,iaf dkfo2 ;2lvs:ns inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If ta.q.0w z(j-- dlznc7 psdxrg 7he same net force is applied to mass 2m, then the acceleration will 7.wsz l. jncddgz7p -(xq0r-abe

  A net force F acts on a mass m andl4 8stosafb 2bh07bc7 produces an acceleration a. What acceleration results if a7l8 b4co70h2 bs tfsab net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will hot4 skho6h ;a2by-5t qp8h d*p0sr d(fly away. This is an illustbh yrh4k (hh8ot*d-5s0s d2to ppq6a;ration of

  Two cars collide head-on. At every moment during the collision, the magnitude n/yhrm tc4.yv*bv-d--9erxsof the force the first car exerts on the second is exactly equal to the magnitude of t *-b mrchy9e v--.dsvn/xryt4he force the second car exerts on the first. This is an example of

  If you exert a force F on an object, d:+ knkw8;cqmk)lm i*the force which the object exerts on you wi:k8mq wikk+c) nlmd*;ll

  Action-reaction forces8qv+cy6 qw mz1

  Action-reaction forces arv)h2u/l 5k7 8iius hzle

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to the r,bz4ci u y7jq;k/uw/car. Since a lot of damage uwqk7zc r;4/j,/yibuis done on the car

  An object of mass m sits on a flat table. The Eartt 9qut ety* s.e81c8dnh pulls on this object with force mg, which we will call the action force. What is c8 tt.*qt9sd 1eu8ynethe reaction force?

  A child's toy is suspended from the ceiling by means of a 5izfmjeoh,w51yd*u3(sy m0 qstring. The Earth pulls downward on the toy with its weight force ofsj,zyw05 f 1*q5oyhiuemdm3 ( 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitchalr33;2l1) j yuj hiwhed to you with a 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose magnitud;jjh y r3) a21i3hullwe is

State Newton's three laay h jt3f3ct/6bnm 6y* q/h/mvws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Wh7d/s n8v;blj oich of the following is true about the mass and vj7o;8 d bnsl/weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at aw5 use5wu6cs: distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person weihy mrdf0gu+2z+*a:p u wfwy2-ghing 600r+ dyyp*2fgua2h0uwwm+ - : zf N?

  A stone is thrown straight up. At the top of its path,,rgd27 nk hn q2dmqvm3;ytv*lib p4+* the net force acting on it imyhvdg 7 ; vpn3nbq2krl i t,m2d4**q+s

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the-crx-ywnk9w -vfsd 7 h/)cl h- same height. Ignore air resistance. Compare their accelerations.l wxrh-ncw9/ dsh)k-7fvy c--

  A brick and a feather fall to the earth at thei4+g1lym**g r pjk-0v xeq(hvmr respective terminal velocities. Which object experiences the greater fyqe0*x (+ l-4vgmm1pkg *vrjhorce of air friction?

  An object of mass m is hanging by a string from the ceilingg .. x 8/li1spfu2vcmk of an elevator. Theks u.82lcxgm pf /i.1v elevator is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the co6kcg, +h 6jg+zvnn( xeiling of an elevator. The elevator is moving upward, but slowing down. Whatn,cz6+(g6xkg j n+ovh is the tension in the string?

  The force that keeps yma,r b64zed,n f+en1k ou from sliding on an icy sidewalk is

  It's more difficult to start moving a heav fj 7smjd6i js*4tm89vy carton from rest than it is to keep pu97mi s4jj f *vtjdsm86shing it with constant velocity, because

  A horizontal force accelerates a box fl( nl7yty scsp,mp; 8-rom rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remait lpmc(n; ,y8sps-7lyn the same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down eyqo a0ui3v.9l .neg).j:i maan inclined ramp at constant velocity. Thus we can de .nj.)m0le9.aqvi3ui :ogaeyduce that

  A block of mass M slides down a frictionless plane inclined at an angle qug2ijpha9 83,jsf ks9 with the horizontal. The normal reaction force exerted3s8j2gi sj9k 9ap f,uh by the plane on the block is

  A block of mass M slides down a frictionless ( 7yz j-nu v.cih*g9pkb/9f voplane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is dirgyfi*u 7.n9cz(9/k hbv-vjo pected

  A block of mass M slides down a frictionless plane inclined at an angle q wnxd fa2f):bj0ith the nbf0fd: x 2)jahorizontal. The gravitational force is directed

  Two toy cars (16 kg aypc );ocwlc46p 53dtdnd 2.0 kg) are released simultaneously on an inclined plane that makes an angw) ;o4pdp lcdcy 3tc56le of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surfw5g4m m3z4adreab/uaoa.0 p0ace. A 16-N force is applied to the object, and itw54pm0u.4zm gab 3 ae/or0 ada accelerates 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. What i+nka5;3xr1fnb 3p) fy -yr rhis the average forward force on the caf5ranbp) kf3r1nr; 3 i yyx+h-r?

  Starting from rest, a 4.0-kg body re 4l+ld9b6wylw rj8;vuaches a speed of 8.0 m/s in 2.0 s. What is the net force actingw;bl vr4d+u98ljl6yw on the body?

  An antitank weapon fit kcqfmulc2mx/d -4 *sy0s w),res a 3.00-kg rocket which acquires a speed of 50.0 m/s after tracy4q- xwku)/dsc*mm 0 2lf t,sveling
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 forg; xctvafv (/e k-(v6jce that you push a 10-kg mass from revvg6vj /fc( e;t-xa(kst,

  What is the mass of a perzj(v *5h1o ,xw.oz r5-vcrfz06)gh u nkvs:ye son who weighs 110 lb?

  What is the mass of an object that weighs 250 N on th.0;lx x m1biqp us0w6he surface of the Earth where luixwb6 p ;10h0xsqm. the acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kgn :q89-f oedgc7;qrcl. er5b s on the Earth. What is the mass of the object on treo9 .n;qcfg :8 -se7 brqcl5dhe surface of 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 B5i/3xjvu ;vu 5fmb+s q weighs 40 N on the Moon. The Moon's gravitvf5/sxm35j i u qbu+v;y is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends ,wg7 jb:vd/mnof a 5.0-kg rope. Sue pulls with a 15-N force. ,mv/7 bw:jgdn 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-8*( +h,kfmrbv2prt qti y1l zrg7p 4h force F acts on the st h*ltz grvibfry 7p8k,+(thm 2-prq14ack, and 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 480 N stands on a scale in an elev; srj3:pkaydbi6: g i8ator. What will the scale be reading when the elevator is accelerating downward at i;b3y6jrak p8g:i:d s $4.00 \; m/s^2$?

  A person on a scale rj2wsy(xpy c84ides in an elevator. If the mass of the person is 60.0 kg and the elevatxycpy4w8s(j 2or 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 rx:)o,xj 23w;q zh kormass of the person is 60.0 kg and the3xrr );oz:,2 ohxwkjq 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 5ymp*nr 1zi3xkrgo03 i* u+v k ik)k bda5,4r.x.0-kg mass. One force has a magnitude 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 acceleration of the mask .d35akbnrki*+y3 mg04vxkr)*i zi,uorx1 ps?

  An object of mass 6000 kg rests on the flatbed of a truck. It is m 28ra :jks8txheld 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 in2m8tsr xa8:j kto the cab?

  An object of mass 6000 kg rests on the zxc)(bzxk(z.ttxk: 3 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 minimum stopping time if the:( zt )xtk3(czbxkz x. load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kz9m +jhx19:cti kwm;ig and m = 0.40 kg, what is the magnitude of th1 h 9:9ixiz;+jkcmtw me acceleration 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 = 0.40 kg, whatpj 89f(l )lddif 6p9qq is the tension in the string? (Ignodp i ljqf9 fl9d()6pq8re friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a forcb;b,zrkdiz ;y;7g)oee/emrj :uvs4 v:e f9 l 3e of 100 N in a directionoyg 7r;4uze/lre kfbb39j: :z)vvdei e,s;m ; 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 horizont3 kpnk0 m)lf)+l-haiqal floor with a force of 100 N in a direction of 37.0e a )0q+ -mk3iak)llnfph bove the horizontal. 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 in Fig. 4-2. mbsuv3f5z6zsf;e 0m - What are the vemfsu 5m6 ;z-3z0fbstensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is m8)1li me0t gu 9i :1ip(bkyaythe mass of the traf1 9t)(iy1g8mp 0iiye m:u labkfic light?

  Two boxes of masses m and 2m are in contact with each other on8a+n)avq so-cni4ku9 u n7j/ a a frictionless surface. (See Fig. 4-3.) Wha7sn+q/4ncj8 ) a aua-iu9novkt is the acceleration of the more massive box?

  Two boxes of masses luz +vzrjg4xltosls) yuz+lazw/x 68 15 *f*/m and 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.)f+z6t81 +zl5 lzulojwx/4/yxsl*sg u*a r)zv What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (Seepkv8uy:6ifbfa 6jeef.s. 2j 7 Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the conn2.jujff6byi ea:s6. 7pf vke8ecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) Iflfz 8gc,t 3dlu5 h3o(a the forward force on the more massive box is F, what is the acceleration of the less c3dau (h35logfl, 8tzmassive box?

Two boxes are connected by a cord running h eeh,vbkxt u*.n192zover a pulley as shown in Fig. 4-5. Box I vuekze hn2 *bt,9 h.1xof 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 b8ncst9 ,k f) (kmkew;metween a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net forn) sk k8kwf(,m;c emt9ce on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wooytb*i vz-7*fod are 0.50 and 0.40,iy*f * -zbt7vo
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 rzs0t oem)i65 a stop with a constan0oeti s6z5rm )t 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 on37lzgpx eh* 5z2zw,z3 fjg3fv a horizontal surface is pulled by a 5.0-N force. A 3.0-N frictiz3v3g, hx*3e5g7 l2 fpzzj wzfon force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest6j nzb:vqq( ud9hu*6 t, 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.qh6(w h 6k8mbe It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction betwek q6e8mwhbh6 (en the puck and the ice?

  During the investigation of a traffic accident, police find skid 3-w/jdz,ob7+fpa97ucj a vncmarks 90.0 m long. T9 dzjw-bao 7n+vupcf ,7c3/jahey determine 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 are stacked. +htfud0r4 0( 6z6lfmrx nlsc( (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 ns(z n 0dc(+h0flt4ux6mfr lr6ot 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 st2gua,thsq y;pm665/ o e-hpsbacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is6 ea5 ygph,omu2th-spq /6s;b 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 fr+ 0xo 1ix*bmutictionless inclined plane. The plane is inclined at an angloi0m1 u+xb*t xe of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hilll/k /sd:ez kj:)wo* qu that 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 inclined plane with a.tq tah(uio..ah j(2w ee(,lin 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 ;ixvw-53we cpqt8c.6 dn;ka hplane 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 dirsydaukg k , v8qn2*.4 /1nudsx1ndt.uectly down an inclined plane, at a constant velocity of xtdsquv1s.4gd ykk .un1a/ nd*u2,n8 6.0 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 roug*lmdo i90e 8zvh $37^{\circ}$ 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 dontq.qtc47m10pek j0:t xig gq,f*9m x wn 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 l1xpu4c r yu lvx7qh.seu02, w6db-(klog weighing 500 N along a rough surface. The cable attached to the 02v.xu 4ubp xhrklsc l q(671-u wy,edlog 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 releas fd-r0ofzqw+ +vzu y:;ed from rest on a rough inclined plane tilted at an angleq+ffru0y+; d z o:wv-z 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 inclineh a1j9lnih-s3xj+3 rq d plane. The angle of incline is gradually increased until the object begins to slide. The angle at whichrq9h+-xhia3jn lj31s this occurs is q. What is the coefficient of static friction between the object and the plane?