Which of Newton's laws best explains why s dktp:em-. ,pmotorists should buckle-up?

  When you sit on a chai g r-8b53 fgj;bx;g:hjgm. xjbr, the resultant force on you is

  In the absence of an external force, a moving obt-o 8c94 ;m 3s0* v4ww,ren gqngeicloject will

  When the rocket engines on ny 9oh3u6vs;pku q5 zs;h vg*9the starship NO-PAIN-NO-GAIN are suddenly turned off, while tr 3 hk56 qvh;yosvgup*9z ;n9usaveling in empty space, the starship will

  A rocket moves through empty space in a straighm 89z amr8kk.ct line 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 rocket in order to sustain its mo 9mr8z.a mk8cktion is

  You are standing in a moving gzalv.w7.t7;lm 3g8drc w7yw8 7pd ik bus, facing forward, and you suddenly fall forward. You can imply from this thdw8v p 78.m 7 7wzwt.yr3glkldca;7 giat the bus's

  You are standing in a moving bus, facinjt7rwut/ pt .7g forward, and you suddenly fall forward as the bus comes to an immediatetwrt. p/7ujt7 stop. What force caused you to fall forward?

  A constant net force acts on an objecz: *36n mu:ne )hpva2 0yysmpwt. Describe the motion of the object.

  The acceleration of an object is inversely pro j- rn15dk*w8y esd5nvqfrg,*portional to

  A net force F accelerates a mass m u q9d tc5wi2fb (bp)i0with an acceleration a. If the same net force is applied to mass 2m, then thbf25ptdi9 (bi 0w )uqce acceleration will be

  A net force F acts on a mh)t)us/yqo8 16;s ,wpdbka um8hedz: ass m and produces an acceleration a. What acceleration results if a net force 2F z:qukumh hba/1sd6oy)pw 8;,s)t e8d acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon willnz j +yksaxco6-3x l-5 fly away. This is an illustk5l ox6z3cjysa+-x- nration of

  Two cars collide head-on. At every momet1nxm9 5v cm- ntsa-t8nt during the collision, the magnitude of the force the first car exerts on the second is exaccn9tts- 8m-1atv nx5mtly 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 exeimkye/ 3 gsk*pt(-dxqc/s5-s)o: 7u mvc2u nrrts on you wi*r cmv - 7ssq(p5gdxkiynu/ )t-/ckm:2 ues 3oll

  Action-reaction forcesx) . elu,0lf(z udqq-a

  Action-reaction forces arzfi+yvkh kkh5 ;l71 0au.so.me

  A 20-ton truck collides with a 1500-lb car a:4y6dftfam:2d jp0wi r aal c:gbp1: -nd causes a lot of damage to the car. Since a lot :rj 1p myd :a:abfcl f6apg:d- wi04t2of damage is done on the car

  An object of mass m sits on a flat table. The Earth pc+gj 3u2ve)f+an+ ag;u 8zp naulls on this object with force mg, which we will call the action force.jaaz3)u v ec8ang2gf +p;+n+u What is the reaction force?

  A child's toy is suspended from thehvtghway - w*:.vp.7t81v2xr z1 vl ou ceiling by means of a string. The Earth pulls downward on the toy with2*17atzxryp 1 h.v-.gwwhov 8lt:uv v its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitchvjyvj1x9+f s 0ed to you with a 1500-N instantaneous force. The ball hits the bat with an instantaneous forc+vsxyj v019jf e, whose magnitude is

State Newton's three ,ht ac9o9xs( olaws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon t9,eevsb x/c08si v +nwh oc.y5han on Earth. Which of the following isevs w 8chosxv nc.5by+ie0/,9 true about the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a hga q, .asmqso 3b7:7ddistance is

  Who has a greater weight to mass ratio, a perso8 n) z*o6cur9utj6pion weighing 400 N or a person weighin)6t i9oznjuo8c*ur 6pg 600 N?

  A stone is thrown straight up. At the top of its path, the net force acting on s7coff. ,0k f3sjukr / eskb(-i f-3fsk,f.7sso(ukbj/ r0 ck et is

  A 20-N weight and a 5.0-N weight are dropped simultaneousta41 20thd1 ky .htqlmly from the same height. Ignore air resistance. Compare their accelera.td khamh10l1 ytt2 4qtions.

  A brick and a feather faln:bs1tvhlr3dj++ r1 +ctu0vl l to the earth at their respective terminal velocities. Which object e1 s0clh:+rr+ul31t b+ jdvn vtxperiences the greater force of air friction?

  An object of mass m is hanging by a string from t6 e0h:n g8 snvg9izynw8tu: m-m(e m;ohe ceiling of an elevator. The elevator is moving up at constant speed. What is the tension in the stringg(e:hzuosg vw8y9;mmn6-n0m8i t:ne ?

  An object of mass m is hanging by a strinf b)dq 9im9uwyp1ud w -t+i9j,g from the ceiling of an elevator. The elevator is dy1fpw)wi9 9bu-uij t,q 9md +moving upward, but slowing down. What is the tension in the string?

  The force that keeps yo g4.sp*fa on m8elhdl2a*th): u from sliding on an icy sidewalk is

  It's more difficult u40k53 lyb ji kmb0q.fz/cg2 kto start moving a heavy carton from rest than it is to keep pushing it with constant vecfgmk50.uz0 bkl jyiqb3 2/k4locity, because

  A horizontal force acceleroehku2 bm0(hfk+cta):+ - ye vates a box from rest across a horizontal surface (friction is present) at a constant rate. The ex)0: koum+h-efhtyc2bv k(e a+ periment is repeated, and all conditions remain the same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an in8lyd4rt7u u ll0g8j,y clined ramp at constant velocity. Thus we can deduce thauld,48l y 07ru tjyl8gt

  A block of mass M slides down a frictionless plane incbo/0kt(vc xw1:uiya /lined at an angle q with the horizontal. The normal reaction force e1 /t0uoicbv yx(:a/ wkxerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclis/s n c(0dn/jdo2ck31ls a b1uned at an angle q with the horiz od0su b2nc(jk/11cndslsa/3ontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an ang92: n umeg:bcole q with the horizontal. The gravite gb:9uc: mno2ational force is directed

  Two toy cars (16 kg and 2.0p 0p9qc76eywj7c kap-)pom +w kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their accelero 7m+y7c-p9ceqp 6apwk 0w)pjation after being released.

  An object sits on a frictionless surf e z9b .-zanr +iq0uk8:pjar7qace. A 16-N force is applied to the object, ijbp zr +:qn rku79a80ze a.q-and it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 10:ok6kk:v4 ywp;v f*hr00 kg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward force on hk*k:vpwy o :f4 r6;vkthe car?

  Starting from rest, a 4.0l f)8r iutj82n-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on the b)ijru f882ltnody?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 m;i 0 0gmk*(fuclab4 lh/s after travelinga;il4(cg lf k0u mh0*b
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-kgk;10; : +uatwl gxsake mass from rest,;0+w:gsel 1kxkut ;aa

  What is the mass of a person who weighs 11021), bkgebiv xohn .e+ lb?

  What is the mass of an object that weighs 250 N on the surface of me 3*wb -3nyp;k, oq p9kc7qlxthe Earth where the acceleration due to gravipqq*cokxm b,pn;e w9 k33-7lyty is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Etqtgct4/ a*h8gi-m iv)4*c9a3 ut fkdkjk:z4arth. What is the mass of the object on the surface of the Moon w *:vg )dkiac3z*gm/t9 k4jtu f i4aq 4ktcht-8here the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, izwb. (7pcp;e and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the ma;7i.b(cw pzp esses of the objects.

  Sue and Sean are having a tug-of-war by pulling 7 cedio)5rg8:/ denn5xca, uron opposite ends of a 5.0-kg rope. Sue pulls withen5 cicxd)o58 rra7d,:e/nug 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 actoemz 0 1hd8.v: kabj)rs on the sze h: doa 01k.vmb)rj8tack, 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 stan5w h2ndesx*d.8rn+v e2c5 ri .u,tzxpds on a scale in an elevator. What will the scale be reading when the elevator is accelerating downward a5.8*r i s2v5dw+ n.t,zhdxn c2pee rxut $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person(x c;,;c bh(ozxgss q7 is 60.0 kg and the elevator accelerates downward wi x(;hg7z,co(;s xsqcbth an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides 5fmoty 2a ,:i8 exj-sdin an elevator. If the mass of the person is 60.0 kg and the:xd,t8jm a5i-fsey o 2 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 5.0-kg mass. One force has a magnitundg5 my7u5ybbe-,0n a de of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6 b,b m-0ye5anudgyn75 .0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests ona(p2an3h 8qxv os1l2f the 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 distance if the load is not to slide forward into the cab? 32aqhfnlov2 (ap xs18

  An object of mass 6000 kg rests on the flatbe sz86c0 ljt 4jaf8p4rkd of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. Wr j4stkp48 0jlf 68cazhen 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 Mu8vd9*4s*kwa6 v wpt)7lvtgv = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleralu*9v6dgvt*7 ) v 84kt pwwasvtion of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown ivr v(j2p 3 p9/f6uuappn Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pulley.pp (u3aru962f /j pvvp)

  A student pulls a box of books on a smooth horizontal floor with a forcelx -i3oty ow72cx ;6jl of 100 N in ax3l ljx2 coyi;tw7 o6- direction 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 with lvxbb :l)o.vw9s 8vnh7hi+u.a force of 100 N in a +vhvi9.b8:xsl 7u)wbn v.lo h direction of 37.0e above 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 8hgh/dw6tf s9):via- cz pe)f,bbxr;in Fig. 4-2. What are the tensions in the9b,xzpfa -8/ dw hics)b t;):6hgrvfe ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is thex3qjkq /ydp 60 mass of the traffic ligyqx /3k0qpjd6ht?

  Two boxes of masses m and 2m are in contact with eachln53sgps n3 i.9*eup0nr fx ,h other on a frictionless surface. (See Fig. 4-3.) What is the accelerats33epnpxg05r.i ls u 9h*n ,fnion of the more massive box?

  Two boxes of masses m and 2m are in contact witqqqs)7xct98pg)2w o5g3 7vfc 6k nheih each other on a frictionless surface.5kv7fq) htc )eg8qpgins3qx 7 9w6oc2 (See Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (Seei,* ,qf+vscda Fig. 4-4.) If the forward force on the more massive box c,q vi+*dfs ,ais F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rraa6e5c,b.1vi .bq;-zi j ecrope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massive-z6.ceae .vrr bji 5;qbca1 i, box?

Two boxes are connected by a cord running over afy.i b gy- x kw8qvc.zfl*t-481 roja4n1yct, pulley as shown in Fig. 4-5. Boxoytf 1 qvgyc,x 8ab -41i*tz48. .cnlrkywfj- I of 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 sta+k9 ggev1m n9i3 ck6gltic and kinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. Wi3+c6vm gnkge9 9 lkg1hat 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 plastic on w8+duyg*qlw8)j 5ji82ry9 b ao1 jgrqfood are 0.50 and g+u828)*9wba rjo jq1fq8dl5j r giyy0.40,
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 to11ak;slj g+ zjh g ,67mt*habp a stop with a constant accela ah bmsgjl17+ 1k*hj;t,z6gp eration 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 foph06 y- xfnn96wq/rerrce. A 3.0-N friction force retards the motion. What is t-nqep hr96 w n6yfr0x/he acceleration of the object?

  A horizontal force of 5.0 N acceleratesqki/,z 1fupfr6r (: kj 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 given an initial speed of 10 m/s.yyfn68mtu8p eq5 + 5hc It slides 50 m on the ice before it stops. What is the coefficientu5h 8cfm 5ype6y+qnt8 of kinetic friction between the puck and the ice?

  During the investigation of a traffic accg/gmza60d )*en tbx+zident, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing conditions. Estimabm0 z6)ed*gzxt/gn+ ate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m artbz 3* cy-fmr9mdo1;ve stacked. (See Fig. 4-6.) The surface between the more m;ov td*- 1r9zmbc3myf assive 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 on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surfaclue2*s p48ps 6g0taioe 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 ius 20si pp4e8 *lg6otas the coefficient of static friction between the boxes?

  An object is on a frictionless incrnx je8:(vt s39zyn3klined plane. The plane is inclined at an angle of e 9s3(8x3tvjny kr :nz$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that mak43:n .f/a yw(ol9)yc rwor71o zbtxpges 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 smoothd:fs+gtg jn51 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 incmj1u*g9 p3r x,(6h n4 xmjfgyelined 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 inclined plane, at a constant velocity zbpomo c-l n(b:70z-dof 6.0 m/s.pb7(zo don-mbl-0 c :z
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 dce /,j jkba*8yown 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 s9 lem6zx+ls,s rqa4vb3(f p4glo0xw /0 2scholides down 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 5+h/(r d):lmsc v pzd,p00 N along a rough surface. The cable attached to the log makes lvpc d+,/h)ms r zpd:(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/s( rk free7,b on a rough inclined plane tilted at an angle of 7 rrfe,bks/(e $33.5^{\circ}$ 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 incline is gradua3qujb5n*tw 0 llly increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of staticwlq jnub35 0*t friction between the object and the plane?