Which of Newton's laws best explains wl-ocbee5px uqo sf,6 vm w67:;k; fgt3hy motorists should buckle-up?

  When you sit on a chair, the resultant force t)mj:s0 v.)wegrqk )qon you is

  In the absence of an external force, a moim11tto:f0:n b620q b-wtfvd sr ft+oving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turne;v9v4 c0g 6bz)9pifm1j.oetg fr5uc /n.w azz d off, while traveling in empty space45fz mb;tgv.. 9 frc/wevz1pa06c)oj 9u izg n, the starship will

  A rocket moves through empty space in a straight line witaaf 76tl0ou1k t1wz 9ih 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 ow9lia16uk oz 1 ttfa70rder to sustain its motion is

  You are standing in a moving bus, facing forward, and youno+/znkdr : )x suddenly fall forward. You can imply from this that k+/zrn :on)x dthe bus's

  You are standing in a moving bus, facing forward, and you suddenly fall forwardci q2t zdluvgou+,bg7;/p 69c as the bus comes to an immediate stop. What force caused you to f do2ub6tcgc il;/vq7,gp+uz 9all forward?

  A constant net force acts on an object. n5a9m w;iwv4tcbt4cls3;i y* Describe the motion of the object.

  The acceleration of an object is inversely3dh dr;5o l7rk proportional to

  A net force F accelerates a mass m with an a wuf:9y13vupm(w g6slcceleration a. If the same net force is applied to mass 2m, then :wvmguw 36u9 (p lys1fthe acceleration will be

  A net force F acts on a mass m and produces an*bwzb.i.)ycl z +dhf51bc8uu acceleration a. What acceleration results d) iuy.1+c* b.lwzhufc8z5 bb if a net force 2F acts on mass 4m?

  If you blow up a balloon, and thspq 8-i7p(d3.y 1 5.zmm2pj izsbr5 nc4af lifen release it, the balloon will fly away. This isfa sfpn.q3 r7dm2ic .l4bi81y-p iz sm(p jz55 an illustration of

  Two cars collide head-on. At every moment during the collision, th5:;has.9qjqv,e jc zsf,5 wfr e 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 is an exajrqv fq, h c 5af5.jz,:wes;9smple of

  If you exert a force F on an obfq.i: .j 3*a(jlpz ,ct qkozn(ject, the force which the object exerts on you wi(zq p.k.nj(l c3*oj,ziafq :tll

  Action-reaction forceswrpp;g+ a0ff:qxac vs.an.+9

  Action-reaction forcnaiivh- 7-p3kix/:hcfcgi1 3 es are

  A 20-ton truck collides wifj9 c9nb3 *wl wmt*il+th a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done on the + jbm9tfni* lw3*9lw ccar

  An object of mass m sits on a flat table. The Earth pullstba9320ke) (rvy vpf 6ail909c yv l;(npacke on this object with force mg, which we will call the ay(l t an3kle9ivve2pc0r (ay6) 0 9k bc9av;fpction force. What is the reaction force?

  A child's toy is suspended from the ceiling by mepmwth)exv1ku) c (lh pb 5 x3(cz18d4wans of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force, lx b)m) 1ehtpw3xu z8hk4c5wd1(c v(p" what is the "reaction force"?

  Your bat hits the ball pitchedk0bb*+j y t:ou to you with a 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose mu0t+:bj oby*kagnitude is

State Newton's three lawsfv1x5bdt)yh 3u9 d. qs.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Whic6hf2*s 1 eq5dnscw8xinwi (/p h of the following is true about the mass and weight of an astronaut on the Moon's surface, ci hwncwsedx 8*si6p2 /1( fqn5ompared to Earth?

  An example of a force which acts at a distwthh 3)f8dyqik/:f0pance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person bxf-w.,ljn lexdy)6j 4cu f;1weighing 600 N cl1bl)j-;6uxf n,ew.jxdfy 4?

  A stone is thrown straie,cxy:yug qi + v 38vgox8d7w:ght up. At the top of its path, the net force acting on it is 8 3::xi7d+qev,v8owxyggy u c

  A 20-N weight and a 5.0-N weight are dropped simultaneously from tyuw11 6 tya6sd7o/hb ihe same height. Ignor6hb6sy da 1oyt 1/wi7ue air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their r/jg5oi*yf mds4j6h +n espective terminal velocities. Which object experiences them h/+igjo6d5js fy*4 n greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. t )p*xww4m*vrk ag 3;eTheeavrwxt4 *;p)*mwg 3k 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 thegqcq (b ge582h ceiling of an elevator. The elevator is moving upward, but slowing down. What is the tensionehcgq( 25 gbq8 in the string?

  The force that keeps you from sliding on an icy sidewalk 8du 2-xuig1qed74e cyis

  It's more difficult to start moving a heavy c-s, ,im-aw6ed 1 hwnlxarton from rest than it is to keep pushing it with constant veah,s1mx-ni elww,6 -d locity, because

  A horizontal force accelerates a box from rest across a horizontal surfac 39t kbu2bor6m7y-k3lwxr4; xqwk n (le (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 happenbw k-k l7t6kuyo 4rl ;xmq(r29bx3wn3s to the box's acceleration?

  A packing crate slides down an inclined ramp ult)tkf 1r8r9 at constant velocity. Thus we can dedutftk9r r)1l8u ce that

  A block of mass M slides do, /a tnvvl*,ouwn a frictionless plane inclined at an angle q with tnu,vla, /*tovhe horizontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclinosrv6uqz36p t6zk9t y 4t (t)ded at an angle q with th)yt z p vzt4rt6k3sd9q6(6uote horizontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane incliqb9l(fqch+ i+ned at an angle q with the horizontal. The gravitaf(q i cq+b9h+ltional force is directed

  Two toy cars (16 kg and 2.0 k smh7h ccgaar(b :,b;;g) are released simultaneously on an inclined plane that makes an angle of 30e with the horizob (;:7h cbr;as,gca mhntal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force /dv-1zch y/vt,t2jxt is applied to the object, and it acceleratz12dy- xcj/vht/ t, vtes 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 slja3dskp;g52hx9qn: / -j lmg. What is the average f9j kgldmpx ;hj -:s/n qla253gorward force on the car?

  Starting from rest, a 4.0-kg body riaoeu )2(, onwpkr1,fq+z o3reaches a speed of 8.0 m/s in 2.0 s. What is the netw r nuk)p,1 ozer2f +3,iaqo(o force acting on the body?

  An antitank weapon fires a s q4o39 cwvfx73.00-kg rocket which acquires a speed of 50.0 m/s after travs97 3o4vxw qfceling
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 r0co meh h-t9 umenq8;9es99mem;no80u- thqchet,

  What is the mass of a person who wey7,s w 3psob(nighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the E ryi/ tv/spdz qd)((9gew0z5 narth where the acceleration g vs 50z(ynqrd)wp//i 9(t edzdue to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the lap kj0mx9t)brb8*a if+;1fj Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6p+0rjjx9am1tb* fa8) i;flb k of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N pt*nwln(k6w;,r b -g.:dih e qon the Moon. The Moon's gravitl-;qitw(b6 e,hd*gp .w :rnkny 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 of kqcbcu*sm/jof4 6gd8 is v :40ztq:w 6a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward ju:zgq q*w60 s :4fm4/kco8c sb6dv tiSue at $2.0 \; m/s^2$?

  A stack of books rests on a e w-(uldmopi0- vttf 3j -pu5*level frictionless surface. A force F acts on the stack, and it accedf 3-0 tm pe(ojuui-w*vp tl5-lerates 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 ycm(5a hh ewh57n.wd4qs:si 6-km uu*on a scale in an elevator. What will the scale be reading when the elevator is awh4(s ikyn 5 wdmc7eum6s5a*.hh:qu -ccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides o r 4gk.fnh9b;in an elevator. If the mass of the person is 60.0 kg and the elen gbfkh;o49r .vator 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 emy go4 mhq*a.4levator. If the mass of the person is 60.0 kg and the elevator accelerates m*oh44q.gm y aupward 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 m+bwbjr d1 mi+k*71lbtagnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.01br +k*1b wd bi7+tljm N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed3r s5kx1nbpy8i7ai ,ug k -f3n 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 dikf3- yunai8 s1brnik,7 p5 gx3stance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is he3rzto8bw 6ea/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 time if the load is not to slide forward into/er 8w3 zabt6o the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what isbtn0l1/pwx6bvrccpq 39 6i- f the magnitude of the a06xibcp/69lqwc1t n fpbv -3r cceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine5e*x31l(c- t ku tyxrh shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignhx5tt-k u1e3(yrx*c lore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of ,-8 j6dmaq6ce qflt s),vlu.x100 N in a dir c)t l6 x.q6dm8-j,saufvq el,ection 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 horizontal floor wia-si 1igu8qk)th a force of 100 N in a direction of 37.0e above the horizontal. If the mass ofiigu8 q s-1k)a 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 supporzx 6:f0hsp mtt my ld.cdjd*/87+.mu hted by two ropes as shown in Fig. 4-2. f/d j:z7ycxmtm*.pd 6mu0d+h h . 8ltsWhat are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 / 7y+7y.jj (/ brzeg+ tgbtuzcN, what is the mass of the traffic7btu/.g7t b (jzjcy/++ygr ez light?

  Two boxes of masses m and 2m are in co t840afpe-m4+3exgcym uh3 w/m o:iumntact with each other on a frictionless surface. (See Fig. 4-3.) What is ou mfwc/ypm+33e g:x-h m4 m8tie4u0a the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each otnp6ug5n iw3la x x, zx9l-q:z(her on a frictionless surface. (See Fig. 4-3.) What is the net fo3zu9ql wgn:i x-xn (5zp6a,xl rce on the more massive box?

  Two boxes of masses m anfm)zx u bna.df n+p 2lr.:h17ud 2m are connected by a rope. (See Fig. 4-4.) If the forward force on tm:d1)hnu+zxfb 2 nr.7pl.uf ahe more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are cd;jk/m178bguvfru5u mk)(5 l cn h/gd onnected by a rope. (See Fig. 4-4.) If the forward force on the more masljb17v/g/mkugc5(;h)u f5 r dunmd8 ksive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running jnu w: ty0-*jjover a pulley as shown in Fig. 4-5. Box I of masut yjj -nw0:j*s
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 and abudez5 m.c(k * desk are 0.40 and 0.30, respem5dcbze.k *(uctively. 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 frl+598etwgs7 bmn;4ga6v x opp ictions for plastic on wood are 0.50 and 0av5po8bp;lm6 7w+t gn4s g9xe.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 d9luqh y:j*)4xpy g. ydd29zpvirection. It slows and comes to a stop wit :pp2j 9yd9g*yhu4dzv. )yxqlh 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 surface is pulled by a 5.0-N force. A 3.0k xlc un5p2v:86kw3gge/ jg)n-N friction force reta pgg5gxcl823n kkvw)6:u/ enjrds the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N ac*s lfmqv*4e/)q3r*zsvj7xe 69o zs io celerates 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 puck is giveh2h;u 5r 9bol u cd1ds(h7n,mtn 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 an,s cdbru5l;2t u9 ndmho1hh7 (d the ice?

  During the investigation of a traffic accident, police find ski9 q+ s6o;bniv 7bto+led marks 90.0 m long. They determine the coefficient of friction bev bibs no6+o+7;lt9 eqtween 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. (See Fi 9j6a.,uhlz c ,xlph6qm afgm8m474fs g. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is roughf44l66ac fagzm h sh,juqm8pml7x., 9 . 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 surfaczw58o oi+w) +l:lt w og;loor*e between the more massive box and th*lz o8+oi :w;wtoo5ow)gl+l re 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 coefficient of static friction between the boxes?

  An object is on a frict r99az yyh2c:xgfq30f ionless inclined plane. The plane is inclined at an angle o9 0yzar9q2fxy 3g: hfcf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill sbq0 ;(hr8dtuthat 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 smoo7we -9 kxzzqh59 hoyp,y(:j fq)1odnxth inclined 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 an x thg2bef343ppj) r-yangle 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 inclined plane, a, *v .edybzw1f/ndlzwvat :j 1o*z5l6t a constant velocity of 6.0 m/y.dv5 1edo,fjzt1* nwa:llwzb/6vz* 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 svp w );: liws5o*nv0zjlides down 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 dom l71auvhrse2t99-wskvmp* 9 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 log weig6*j:bjrag c r)hing 500 N along a rough surface. The cable attached to the log mjcr6) *r: abjgakes 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 cy-brk(/cg:epv t1lstc68wh ) i-c) tfrom rest on a rough inclined plane tilted at an angle occhtl1)ev(twit-6g cskr-yp: c/ )b8f $33.5^{\circ}$ 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 dpm 40(:xxubv plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is x0: xdmup4v (bq. What is the coefficient of static friction between the object and the plane?