Which of Newton's laws best explains why motoro*az- kbt z zo;ylo5,,rolex)p a 58e(ists should buckle-up?

  When you sit on a chair, the resultant forceg+4.hq ob *odl p0y:cx on you is

  In the absence of an external force, a moving yf*nkc* w0ztt;nb 7) yobject will

  When the rocket engines on tuv 1o+1*g rutzhe starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in e uuor+1vz1gt* mpty space, the starship will

  A rocket moves through empty space in a straight line with constantv+9txf- e ,rbhtnhnfpc+0:x+ speed. It is far from the gravitational effect of any star or pl:xn+ n,thhff-bpcte 9r0 x+ +vanet. 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, faci8n9kun i zv6 v cg9/m/y5mfth:ng forward, and you suddenly fall forward. You can nvgn/v: 85m6/imkfc u ytzh99imply from this that the bus's

  You are standing in a moving bus, facing forvhu+ t-:fjdpw1g5*2 qdjlkr s jd/*)sward, and you suddenly fall forward as the bus comes to an immediate stop. What fgpj*d )v: /ls25qujddfkj+w*1- thr sorce caused you to fall forward?

  A constant net force acts on an object. Descdu,ecm8csyws.j+v:..w qei9: z h8k mribe the motion of the object.

  The acceleration of : .qc)orssi 5d1* ozxaepd8++ljq r7kan object is inversely proportional to

  A net force F accelerates).50)d-uevzl jq. mz- 5jxlwqy syyv+ a mass m with an acceleration a. If the same net force is applied to mass 2m, then the acceleration .yswvjylmy)q)5 eqz- z-0lu +j5xd.vwill be

  A net force F acts on a man w9a-wdwmv d ,k/xznk*r(7 8nss m and produces an acceleration a. What acceleration results if a net force 2F acrwdda-,nk*n z w89 ( /nkvm7xwts on mass 4m?

  If you blow up a ballo/ bsfz+:af2fpon, and then release it, the balloon will fly away. This is an illustratbf fp+f/az:2s ion of

  Two cars collide head-on. At every moment during the colc t85a s+u.ib :m4giaklision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitudeimg i:u+bk8ca s54.a t 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 whiche ho93v-a4gbw4gup ; h the object exerts on you wi;g4u4wvbp h -e9hoag3ll

  Action-reaction forc3:q aww;wk( zt,nes:kes

  Action-reaction forcock1r7w7 -c)-y ihopves are

  A 20-ton truck collides with a 1500-lywtopn9 j5xr- -0h*irb car and causes a lot of damage to the car. Since a lot of damage is doneyh*0oprw x-t n5-i9jr on the car

  An object of mass m sits on a flat tab -xnhlldu.vt:bk ,:3ple. The Earth pulls on this object with force mg, which we will call the action for- n,:d.t l up3vklxhb:ce. What is the reaction force?

  A child's toy is suspended from the ceiling by means of g gd5zjxkbz9 . j66y4wa string. The Earth pulls downward on the toy with itszjk9g6w zbd65y xjg4. weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched vsy bk;1h 3wa.t+qif( to you with a 1500-N instantaneous force. The ball hits the bat wis t1 v.wkf;(+aq 3ibhyth an instantaneous force, whose magnitude is

State Newton's three l)p+6:jye gx7a2bo xyoaws.

  Mass and weight

  The acceleration due to gravity is lower on yh .(r e*q97g pt+54mzlsnw nkthe Moon than on Earth. Which of the followinnw*pznls 4h5gqe .(9mk7 rty+g is 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 distanceog jgksq; f.0/n ,as *qfc,op8 is

  Who has a greater weight to 5y m)khgu4(wxb2mlv- mass ratio, a person weighing 400 N or a person weighing 600 N?54kmyvlgm-w h)2u bx (

  A stone is thrown straight up. At the top of its u: x)..cksl*b)kn3erybd gu; path, the net force acting on it br b *c3ue)kkd.l) ug;sxny .:is

  A 20-N weight and a 5.0-N weight are dropped simultaneously fr7b8uwdn 74so cdb8 2bmom the same height. Ignore air resistance. Compare their accelem8dd nw8bb 4 bu27sco7rations.

  A brick and a feather fald:exgrr0ez; / l to the earth at their respective terminal velocities. Which object experiences the greater0:rzx /eed;g r force of air friction?

  An object of mass m is hanging by a string from the ceilin:tmm5ty8,(hbn8ls x ,r6uy plg of an elevator. The elevator is moving up at constant s 8:u8mp6r5lm ty,l, bstx(nh ypeed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elevx 5l rmcbtf7119aiu 4wpossl4+9 uz4fator. The elevator is moving upwa 9x4lsb tuf5s94l 1ui wz+7oa1p4fr mcrd, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on f d (j7b7.fuue s:,unaan icy sidewalk is

  It's more difficult to start moving a heavy carton from rest thac*. ap-r71 zu pvrdv0jn it is to keep pushing it with constant veloci*0vr.7-1pdcpvja zru ty, because

  A horizontal force accelerates atwu a+m :0gb9it ujwa r(x:58d box from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions re x5u:9 m( dr0w+ta: g8iatbjwumain the same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velozj4gv i(3z hsu8ezy 7zc:r )poa ;3q.ycity. Thus we can deduceos r iyz zcp:) 4 ay33zuv7;h(gj8zq.e that

  A block of mass M slides down a frict. h4xkt 9k0fjhionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by tt.0hhf4xk9j k he plane on the block is

  A block of mass M slides down a frictionless plane vz 1 hqcpfy(*p+to(e5ih2w-ng yf2+z inclined at an angle q with the horizontal.n5 (v 2 *pze hfwof(+t+zyyih -cq2p1g 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 angle q with thxa*4 6 evt1tshe horizontal. The gravitational fov 1eh t*sxta46rce is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclineda.afz3eww8vdy b; . ;f plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being relwa.b.ydf8vz ;f 3ea; weased.

  An object sits on a frictionless surface. A 16-N force is applied to the objectm.7csakny( tqv.jk 8hc)2ov fc +u* lr oq-.7c,uoj+*-akchykrv..2 tcqlns c ofvc7)qm8. ( 7 and it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate fr46i9 zjnxtv3ez)p./ yqs ,wdl .qotk*om rest to 27 m/s in 7.0 s. What is the averagt9pxq.n lyev,34)wsdk j/z otz6 *q.ie 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. What i qdcy0r6azgyg4jg// ( s the ne46zay ygcj(qg0// g rdt force acting on the body?

  An antitank weapon fires a 3.00-kg rockv-h sq6f;c;3xa f-pxz/) myhiet which acquires a speed of 50.0 m/s after trava ; fmyf6phx3/s-;hq v i)c-xzeling
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 t 2o*sy6kcn -d3c-xj2dr) btfe hat you push a 10-kg mass from resy tc)nbd2kre x o3 2j*-scd-6ft,

  What is the mass of a person who weighs 110 lb 45)ffnfqa b4bg:j+ht ?

  What is the mass of an object that weighs 250 N on the surface ofu8bx(9 - )ifgnbra * 6joq;p*ffnt 4cd the Earth wheref(qn -*g db)r*jnu896icp;a offxt4b the acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Ear 8 nwccv;gc 3g;j,*/l )wlkbpgth. What is the mass of the object on the surface of the Moon where the acceleration due*pc bwjl;nv3 , clk cggw;g/)8 to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 xb-oxg *g:a5b0l8bf sN on the Moon. The Moon's gravity iss* boxf0xg -alb:8 5bg 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 oftiuo8ay (n(s m/z,oj :ud by24 a 5.0-kg rope. (zb,4 /s d(uaon j ymo8y2t:ui Sue 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 acib)4zji; cx.tr. 1lrn ts on the stack, and it acceleratenrrji) 14cbt. l ixz.;s 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 dlk+rx8f txf jxxj,a0. )g ;f0an elevator. What will the scale be reading when the elev. )afxrf+f 8xxtdxkj0 j l;g,0ator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person w c 6oem5o(pj:is 60.0 kg and the elevator accelerates downward with(5oo c6ej:p mw an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. Iiv1 1dsj0p1el,zm/e1lu g v:d f the mass of the person is 60.0 kg and the elevator accelerates upward with an adl dvgv:eis1, jlz/ 1 1e1pmu0cceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg masse*fccv:cp.p) )p k4:emq v2hfv,vgajd7o )1d. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude ofv f*o.qf pg)v:) pav hev 7km:p4c2cdecjd,1) 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in j( .+b db-u(zjycy t,tq.o8zqplace by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, what is t j.yyuz-(b, q(j z+.b8tqdcothe minimum stopping distance if the load is not to slide forward into the cab?

  An object of mass 60v g yoa*6k1c0a dc4yw5af69+7 enjbhf00 kg rests on 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 time if the load is not toa dy avwy0h665o*n 7a1cejfk 9c4bf+ g slide forward into the cab?

  In the Atwood machine sho.pfz-co a5h4h wn in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the accelerationp5hc4o.ha zf- of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machinuo7b -19vg u ex10d37uddq dgma q:my(e shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the ma- ebq7dm:o1 d9m7q3yg0u au(gxdvdu1 ss of the pulley.)

  A student pulls a box of books on a smooth horizonjf0xjk2x1v (w 7j)bznjfxm 5 5tal floor with a force of 100 N in a directj v5xzxjkbmw0j)5f 7(2nf1xjion 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 a fe+titl f;4ncnelhwq g 7:r*) 3kg 80s;2jyypc orce of 100 N in a direction of 37.0e above the horizontal. If the mass of the 0*t;gil jngn+8cfryh2pklwct ;se:4q7ey)3 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 a 0,lk we cpt)g,8cf*its shown in Fig. 4-2. What are the tensions iei*k0l, tcwfg)t,8pc n the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of thec4-w:e(va kfp )l xz4c,e qk,s f--hsp traffic light?sxe,: 4,c kkw4c(--qa)hvf pzpel-fs

  Two boxes of masses m and 2m are in contact with each other on a f9rllthx40x i3l1zs kz flov xm8f,.2) rictionless surface. (See Fig. 4-3.) What is the acceleration of.ozt) s,x3lvx1l9mz0ri82xl f lk fh4 the more massive box?

  Two boxes of masses m and 2m are in conta0 uf b24y7 e5*jk0tzqbcxojma 3b9 c4zct with each other on a frictionless surface. (See Fig *j x3b zao2zkftqc cu7ebb0y4j940m5. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected rt/ w z9.)uy ).b5fuvjsaldo,,d2ve oby a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in theat,oo/.ruw5v.ze)dl92d j bs)f y,v u connecting rope?

  Two boxes of masses m and 2m are connected by (-fa0dqmhsm1 a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massive bo-hd(qa1fmm s 0x?

Two boxes are connected by a cord running over a pulley asmy8*z7 3nwr ,gxt p:ym*yz3tj shown in Fig. 4-5. Box I ofjytyg*y,z8mw n3 z:tp3r*m7 x 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 k *q:axf 9 :gp*unwdqb.inetic frictions between a 3.0-kg box and a desk are 0.40 and 0.u*b .w g9a::fn*qdp qx30, respectively. 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 plastic on wood ar5+u:psf iy;1l 3qkho0,j d xlue 0.50 and 0.40 ,jxly 0qods1+:;ul 5hpk f3ui,
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 directionqbcsug0qrc8 p 2l-a84h ()uqbzw ix,. . It slows and comes to a stop with a constant acceler8 cs puqawx.b)gcu20,-qrlb4q(h i 8zation 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 forcenn* 3(dby,76w:ceb5 ep zd dpq. A 3.0-N friction force retards the motion. What is(d*b3 pd:cnne 6 byep,dz w75q the acceleration of the object?

  A horizontal force of 5.0 N accs k/wo6n5ty+gelerates 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 initial8xbt;s yh)wwb7c;.kx rbe e1go2z12 18e tuwe speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction betweewy;te w)s2 bhg2r8;webxt7b1u81o cxe k z.1 en the puck and the ice?

  During the investigation of a traffic accident, police find skid myfyu);oe / mv8arks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.;/u veoy)m8 fy500 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 Fig. 4-6.) The surf hx44qwc7 lawb7fz0ednl; r )7ace between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less massive box doeswn4l)l4faq7d0 w erhb7x 7 z;c 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 surface beta)dnoi 78x rmdhg-nzcn6 kn 449,insnx9l 7(tween the more massive box and the horizontal surface is smooth and the surft -7cn7od (z)ndg sk4n4iiamlx 6n98rxn n9,hace 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 frdlfup 6biav6d(c(5yporpo hw05w+; 4 ictionless inclined plane. The plane is inclined at an angle off0(awvi r5d5oc6 y( od4p+bp; pwul6h $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a fls -zngpn2fe 7,at hill 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 plecypf5 -q-e.xsrtij n( 2ne5q2h8ks *ane 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 inclined4ac1d;c r1 uo )8d+ vhbu)qzwu 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 constankga n+1*88 sk1ewgitet velocity of 6.0 m/sw8gk+1 anke sgt1i*8e.
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 s 9-;lx v f(j)v)mdnwtclides 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 sli2)hi58e +pwt41 hobsz m9e kwqdes 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 500 N along a rough surface. The cable attac9uis c j*lf3cdr nqp ke 1y*cow-a-729)an:athed cr*iea apy-1c72d olf)3nu-q9:t*nsa9kj cw to the log 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 fromixoq1 ik d:wgzvw(1 js 1r2n8cgb.43*jue9yt rest on a rough inclined plane tilted at an angle ofyrbnvi9 x32gi. ue1:g(wcos11 *4kjqz8td wj $33.5^{\circ}$ 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 incliqk/x;nh2fabnm/j 5,c,dxt: z ne is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static frictio/b xx ;2atjz/df 5c nh:q,mkn,n between the object and the plane?