Which of Newton's laws best explai7ojre 7s- ewj)h61yuqns why motorists should buckle-up?

  When you sit on a chair, the resultant force on you tjf d1e)l9tuyub yvov;e m2-m q0*w;:is

  In the absence of an external force, a moving objzc op ;l9*j*nttt60b vect will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turnedauc- *zcv2,da off, while traveling in empty space, t aaczvdu*,-c2 he starship will

  A rocket moves through empty space in a straight line with conuopjk:b tq /88stant 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 susk8q8 bpo: /jtutain its motion is

  You are standing in a moving bus, facing forward, and you s5ksl-i as5 s*iqk65v suddenly fall forward. You can implk ssasi5qs6-*k55i lv y from this that the bus's

  You are standing in a moving bxni7btp+ 8da -us, facing forward, and you suddenly fall forward itp7x+8an db- as the bus comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of b6l0fe: 6 2qgqf9r/qcku f s1lthe object.

  The acceleration of an object is in t,jl(h ny 89ga:(9ps.pploh hversely proportional to

  A net force F accelerates a mass m with an accelerat.d2k+o e-b5tkg33a thmz :h pdion a. If the same net force is applied to mass 2m, then the acceleratht : mo+2-ht zbk3.ae3kpg 5ddion will be

  A net force F acts on a mass m and produces an acceleration a. What acceleral (3pbli btu:e) ;z:vztion results if a net foriu;tz:vpzell)b:b3( ce 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon wiln(mcsc0p a gos/(zr 4f+f4tn. l fly away. This is an illustratio+ 4fnrso m/pct s f0ga(znc(.4n of

  Two cars collide head-on. At every moment duri 5 v7x e63col,vjpho*lng the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of thloh5*73lx ovvpe c, 6je 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 exe)w 8udj9txoep0 o7(xlt.q u6/ ntt :hfrts on you wiloh6 x0 (t.t:/8 otd) eq7jn9wpuu xtfll

  Action-reaction forceedvvvw m )00lbr.,:gzs

  Action-reaction forces ar0mq6apg; etw :e

  A 20-ton truck collide tjk,3nkm:aw2 +trrr ;1 6yawms with a 1500-lb car and causes a lot of damage to the carknr:j2wmra;3 + tw6 yt,m1k ra. Since a lot of damage is done on the car

  An object of mass m smy+hgpqb(;wm 0 g67writs on a flat table. The Earth pulls on this object with force mg, which we will call the action force. Whatbh+0;wg 7r (y wpgm6qm is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. o 1jiummz lh s)i3mb 4i0e+65sThe Earth pulls downward 6li1imesm 0 i)m45+js zbuho3on 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 afl;z u8f2cryn2;.jeycq, * *guq hq7g 1500-N instantaneous force. The ball hits the bat with an instantaneous force, wh q78.c ;f*zrqu huyjyqeg2*;c n,2lgfose magnitude is

State Newton's three lawv4obds:l.2/;lvxsn z .k owm :s.

  Mass and weight

  The acceleration due to gravity is lowerk5 m.jpigwp p5o+h, 2f on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, com khp 55pj2po+iw,g.f mpared to Earth?

  An example of a force which acts at a d3bh39s: *: : vhcpbo h*dzoemyistance is

  Who has a greater weight to mass ratiof6ww*c 5cz :gc4vmp2iw1e1 wk, a person weighing 400 N or a person weig c4v2wm1igc wp fw561wc:ek*zhing 600 N?

  A stone is thrown straight up. At the top of its path, the net force acting on w0tnw:zcexb h+p3ji 5(g 6ns3 it is3: t0(cnniwj5bp3 x z6hse+wg

  A 20-N weight and a 5.0-N weight are dropped simultaneouslu -5ujik1oi0jdtt+n+. h xrb+ y from the same height. Ignore air restk 1 xd +u-r+5 nijhuoj.ti0+bistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respectgdiv o5 s-f*qau)4bk9ive terminal velocities. Which object experienceoiuk-db 4)gq5f9va s*s the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an e1z1a uq(pc89ukzm-3hi :ny ly w q2(oolevator. The elevator is moving up at conaqzc8-yy:92zqlu(kpi11w( noo h m3 ustant speed. What is the tension in the string?

  An object of mass m is hanging by a string f5/ f h+cg:uak5k8d ,/c viwqiwrom the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the vu:8ic+i/q5c5ah f w/kwk ,dgtension in the string?

  The force that keeps you frorxj363y b*eor7v. m gcm sliding on an icy sidewalk is

  It's more difficult to start moving a heavy m ,a+tru.krd 9c( p+kicarton from rest than it is to keep pushing +cp (d.t arimu+9kr, kit with constant velocity, because

  A horizontal force accelerates ycjw+t e6(lm.gaqi-:vwlx5: a 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 happens to the box's acqw t: (+me-l5yg6alw:vij . xcceleration?

  A packing crate slides d*mglk21x) f ltomr08qown an inclined ramp at constant velocity. Thus we can deduce t*t 0m xlgfm2o18)rlkqhat

  A block of mass M slides down a frictic,)b8dk7mr ubs+wujih/ -3 0x0dvn g tonless plane inclined at an angle q with the hdn 7skb gh3im+uxt0udbc0)8v,/w r j -orizontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down zej9b8z8o4 f :kp eusgu;--ona frictionless plane inclined at an angle q with the hori-ujfk4nzz89sb o:8o;- egue pzontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slej, wu u3p zh(fuln1qj(j; gl.dr/53cides down a frictionless plane inclined at an angle q with the horizontal. The gravitational force is directrle( juz;fl dg,jph5u(ncuj . /w1q33 ed

  Two toy cars (16 kg and 2.0 kiu(zhw+c+bngn ( 8fne, tsd; .g) are released simultaneously on an inclined plane thatn n+;.((c +udn, hbe8it zwsfg makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied f/a rl:3xneg7 lgod)*to the object, andl:ga/f *od 3) 7gerlnx 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 rest toyi0va0,.dx 8o,o3st +/i4rmy p jfzml 27 m/s in 7.0 s. What is the average forw y.xvmlp+om4i0ft /i8ja0 3d,yzr ,soard force on the car?

  Starting from rest, a 4.0-kg body reaches a spezbf5 g+o lyzz6;81 ytfed of 8.0 m/s in 2.0 s. What is the net force acti y5fb t1zzz86loygf;+ng on the body?

  An antitank weapon fires a 3.00-kg rocket which acqu2ntl ljlzrg1w -):u,t qu3zv-ires a speed of 50.0 m/s after travelingr 3l ztlgv-t,:nl)1wq-uj 2zu
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 mu17j5k9kliqmr sfz -y2(e4 ei ass with the same force that you push a 10-kg mass from rest,ulk5 e4ek9 r2j7i-fzy1si m(q

  What is the mass of a person who wei2j2n3v xp c3km1jd*b9d qobl5+u ih1 bghs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of8w3pdtb2h qy 5.ac x2cbasp(: the Earth where thed.ap txy5bs b 83ha2(:pcq2c w acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the object on :fnhtgia5: 9zbu)z0(f kvib7 the s 0itngi(vkb)a7:zf9hz fb u: 5urface 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 B weighs 40 N on f/a ngiidc1p o /jd66+the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of o+ci 61dni6g d/jp/f athe objects.

  Sue and Sean are having :ze5h5pgxx 5s rhl k1)a tug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N x:s5ghekrh)5zx 1pl5force. What is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a leveld mw*h ;oytd( ub9/o)o frictionless surface. A force F acts on the stackmh o;(od tb/*wd9 )uoy, 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 enp; psmn+5e6 j wnd f( *vo8pp8x8tr3stands on a scale in an elevator. What will the scale 56e8dpojv;e*+tn smrn3(npw8 xppf 8be reading when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60keuek /h35 x72 p nv0.trfdv+k.0 kg anfpk xe3rvk20k+5 eu 7h.v/tdnd the 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 cmz40 nnrf4;.u6fd fvthe mass of the person is 60.0 kg and the elevator accelerates upward with an accelera 0m;.n d4c n4f6vzfurftion 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 of b5v f w5sg 5w ai*g m-5wutf:phgpg6+78.0 N and is ugp 5vm hf+fp5w7-gbwgt 6:iwga*55 sdirected due north. 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 5qv lxj4 ,5:twhmh-otrests on the flatbed of a truck. It is held in place by metal brackets that,ol mvth- qtj4: 5w5hx 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 flatbed oj7e g*3ptt ww+f a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the +ett*w 7w3j pgtruck 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 = 0.6 t yoq56w94uwd0 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction uy tw9w4doq56 and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and xiy2g+p; 9(pwpvzn/d.xr5:cxyoe s 4m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass xyc2 w;reps :x zpyvodgn x4+5 p(9i/.of the pulley.)

  A student pulls a box of baw i9bpg 5g(v 0l/f6 7m5ymiahooks on a smooth horizontal floor with a force of 100 N in a dy(iwg5/ fi79ba 5lp h60gamv mirection 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 bmujcm 41q nt /1.u7cseooks on a smooth horizontal floor with a force of 100 N in a direction of 37.0e u/ c s1jq1 m4.ucmtne7above 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-bblb p 1wj0f:at.:/iv2. What 0jlv:f:a1bp. w /bitbare the tensions in the ropes?

  In Fig. 4-2, if the tensions in the )efszj;dyvoy 9e0,f mf 1o.c2ropes are 50 N, what is the mass of the traffic y;f 9o.f2 yj 1,fee)svozc 0mdlight?

  Two boxes of masses m and 2m are in contact with each other on a fqvqz33 vx/8dxnvm 7 8 9ycjk9wrictionless surface. (See Fkxqn33 dcv78 zw/q 8vxmj9vy9ig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m ayci /k7d0b z3ure in contact with each other on a frictionless surface. (See F 03dbk/7czuy iig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connectedea6uyvt5 41 +r; zbyzg by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the ugv;b a1erz+4 5t6zyytension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See F -8 vlrrhd81rnig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massive bdl-1h8r rrnv8 ox?

Two boxes are connected by a cord running over a pulley jv2 c8m );svjkas shown in Fig. 4-5. Box I of mam c2vk;vj8) sjss
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 x 5wob)le ;r7ea 3.0-kg box and a desk are 0.40 and 0.30, respectivele 7orxe;lb) w5y. 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 frictions for plast*x1otptym78lv w:ht. ic on wood are 0.50 and 0.t1w8 *vxthy :.pt7mlo40,
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 x9 q3ine9h tvj+jz51tslows and comes to a stop with a constant acceleration of -3t9v9t e1+jj qxhni z5$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizooyf -7 e i;u5athn5 9ba75hbdsntal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of the obh5io7y97 euh s;a5 d5bta -nbfject?

  A horizontal force of 5.0 N accelerates a 4.0-kg px196cts1 c epxv.9qh ml)7fdmass, 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 gp) g9ss 0 ay, u/4r62g z51voztgfmtwhiven 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 thehvwayutz grg6fpm2o /)t5s0 z41g9, s puck and the ice?

  During the investigation of a traffic accident, police find ski.bivlcn(vq4 ze8) zc+ d marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadwe8b nz+qi (lcv .4z)vcay 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. (Se e-fjn+fkq3 h)e Fig. 4-6.) The surface between the more massive box and the horizoej3 f+) fnhk-qntal 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 on the less massive box?

  Two boxes of masses m7x5qr7m)qa/ p xzk+st and 3m are 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 matp xar+s qxmqkz 7/57)ssive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is inclined at anq q 1wgs:6 owmci*m2x8 anglesq2o16qwg i :8*xmcmw of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makesy n0jx,sqps o8g( -4iz 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 incline/f:l ko j 0f7fyvdk95fd 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 incl nqs onuw(/3p0ledi/)ined 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 inclineds nx9 x+prl4,k3)j pjm plane, at a constant velocity of4jr j3kl m+pxp ,)x9sn 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 mass2grj2pit)j9a7e7c*j, le jk d m slides 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 down a rough )wujy9 a ap k2-g-opg0an;o l9$37^{\circ}$ 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 500m4r.brh4 pz* s N along a rough surface. The cable attached to the log makes anhmsprr . b*4z4 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( u cv ,tfw+)akj6u4y 9aroh*z rest on a rough inclined plane tilted at an angle cu6vh9)* yaaujzw4t (k+, froof $33.5^{\circ}$ 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 inclecjy0zvo8q qy;u j6d :2c.sc,ine is gradually increased until the object begins to slide. The angle at which this occurs is q. What is thqccd,cquy sy0 j;:zj6 .eo82ve coefficient of static friction between the object and the plane?