Which of Newton's laws best exikeg cgn+6u 8w;*q;7 vvxhkh (plains why motorists should buckle-up?

  When you sit on a chair, thloginr+;m/ rorjl .;x 3db4+i e resultant force on you is

  In the absence of an external force, a moving objepn; q wl49p0fu2+:altgxdw7xn 1b*raa4ei )sct will

  When the rocket engines o z(oz (z/wun+cn5r7 i+mf;cxtn the starship NO-PAIN-NO-GAIN are suddenly turned off, while travez;(m o rn7 c+zf w+u/ncz5xi(tling in empty space, the starship will

  A rocket moves through empty space in a0;:flicn1zh uco*, gn oswt9/ straight line with constant speed. It is far from the gravitational effect of anlnz*co;on 0 fwi sc:/tu,91ghy star or planet. 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,9 lmhra fn):pk1 ni s+/j8fvl) facing forward, and you suddenly fall forward. You can imply from this that the b+ h j n1mafp:r)li/sln) f9kv8us's

  You are standing in a moving bus, facing forward, and y.k cwl y6mpc,9c ;4gmnou suddenly fall forward as the bus comes to an immediate stop. What force 4l.km; ccwy6, p9nmgccaused you to fall forward?

  A constant net force acts on an object. Describe c/k f4*yhb kca hvyb6 *if:st8bqa7+*the motion of the object.

  The acceleration of an object is inverselz 2. osiike;fkcw;u)c vz;rk ym w2/)8y proportional to

  A net force F accelerates a mass m with an accelerwur+hm yaf(i)w0cy6h7r*-qne2 ati clfz 0) 5ation a. If the same net force is applied to mass y-)y)(rc0 wa cm7w f i+i20*hruh5n zeatflq62m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleratig(0 6jle0njt ( l:g+kyg cl n5v(bmc:xon a. What acceleratioe v(: :jnlx5blc0jgm0 g6 +ngkcl( y(tn results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. 5km4iv0cbbq-+ju1y9 r1ypi7 i yzs8f This is an illust0yvu9 +54kmbyb8 jcsi7zii-1 q1fyprration of

  Two cars collide head-on. At every moment during 3a t/aq 9iq9hfvlh5a(the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magh9 vhq(a5q t3ifaal9/ nitude 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 epr k)q:a2n9 -n/uqs 1p9vsjralt*g7 force which the object exerts on you wil9eanp s -/*pas1:29u r)kqvqr jgl n7tl

  Action-reaction forc *s2nz :3a8ikqxum:h ges

  Action-reaction forces areyn: ew4( k8njbab2p py8f5sf 8

  A 20-ton truck collides with a 1500-lb car ;;hx)w;o ngfi-m q0wnand causes a lot of damage to the car. Since a lot of damage is don- niofw ;xn;)hm;w0gq e on the car

  An object of mass m sits on3xf(dan m+r ,r a flat table. The Earth pulls on this object with force mg, which we will call the action force. What isd r+a(fxr,mn 3 the reaction force?

  A child's toy is suspended from the ceiling by meaz 6q8)zca4wrpns of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reacqr6z )zwac84ption force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneo.ci-l-ecf3 bg us force. The ball hits the bat with an instae- 3g.cbcif-lntaneous force, whose magnitude is

State Newton's three laws0 9mz9tq.t 4iza51k5h ezlx ay.

  Mass and weight

  The acceleration due to gravity is lowerwg2szeb rt2r wz-+xx(;b 2t5y(ign s; on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on tw; +y- r(eb2; 2n5wri( 2xxgbszgsztthe Moon's surface, compared to Earth?

  An example of a force which acts at a dy4y:cx6q e -bi:ov2n)wvb +fristance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a p lgzp44sua3mhfg5vvd)8/ 9jkerson weighing 600 ug45/34kmv)9 j ds vzg8hal fpN?

  A stone is thrown strain7pim ymk9,e : (9iybight up. At the top of its path, the net force acting on m 79 mpk9(ibiy:y, eniit is

  A 20-N weight and a 5.0-N weightg/ 5z8-9a8dyervzm et a 5ym,x are dropped simultaneously from the same height. Ignore air resistance. Compare their accelerations v xegady-a5z9r5t,y88m /mze.

  A brick and a feather fall toqprbi5 p, mq57pys4.w the earth at their respective terminal velocities. Which object experiences the greatpp, pq5 m.i75r4bsq ywer force of air friction?

  An object of mass m is hanging by a fpqii* )qiqe49.s jw:string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tensionjpi)i4 w.: esi *qf9qq in the string?

  An object of mass m is hanging by a string from the ceiling of an elevatht1qncn;zu07* 19 g0yrvhjicor. The elevator is movinjrcut*9 n hgq y01;vi07c n1hzg upward, but slowing down. What is the tension in the string?

  The force that keeps y3n(p y9*rip 0v6kz mfgou from sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton 5 tb 1:eda ewrdz6/ta9from rest than it is to keep pushing itzeawde/b: ta56 d91r t with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal ahoy/ 9paon*0 s13+y0 7og djjd 8 tvgzld30fasurface (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 hahplo/az1y3oy nja3+g00fs 8ado jg9dtd 0v 7*ppens to the box's acceleration?

  A packing crate slidesgqc o v1,xcs lfk/*+k, down an inclined ramp at constant velocity. Thus we can d,1fv+q*, cxkkscol/g educe that

  A block of mass M slides down a frictionless- (rq hnrda xc, )-q82tj/shch plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the blocd2,/hxhcqart )hjr(s-n c q-8k is

  A block of mass M sli4c/8:ltt aj(zv8o fqaai(y /xdes down a frictionless plane inclined at an angle q with the horizontal. The normf8// zi(ota(ja:8x4 tq layvcal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclifvsjxv81x 4,f ned at an angle q with the horizontj,s1x v f4xv8fal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released cxr41wda rx 0y0i6fm 8 wqp+r(*kilb- simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a s-fw6wi4 yx0x rabkc plmd*0q(i+ rr18tatement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is appli9i6i)b ix:y5laf ;zrced to the object, and it accelerata;lc i)6f br 9i:5izyxes at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 knd:gc660 jwm bg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward force on the car?w6: 6bn djmc0g

  Starting from rest, a 4.0-kg body reaq074y8 xz 1(vds zqkjkches a speed of 8.0 m/s in 2.0 s. What is the net force acting on the bz7d1yj0sq vk 4xzq (8kody?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0e*e32lxme fn9q5ve v0 m/s aftexe05q *3e 2m9fvn elver traveling
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 masg-av 8kp::n)ldwqj t3t ryr 0/s from rev 0 ):tyrgln3kjd8-pw:t/q ra st,

  What is the mass of a person who weighs 110 lb?3inas ,6mx(uci 3g*wy

  What is the mass of an object that weighs 250 N on the surface of the Earth whececso/qj: 1 ,+y0ca qnre the acceleration ducyqenoq0,csj 1+: c a/e 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*h2x0 (mxjc456hdiz( rdgq ol object on the surface of the Moon where the acceleration due to gravity is only 1/6 of that on the j cmh65 (x2 ldzg(rq4* o0ixhdEarth?

  Object A weighs 40 N on Earth, and object B(jz50kzj/+51c ritehj4qi z,lt , yo13frqg f weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of the objeqrt lqf,3g51t0rjh fy i/zcj kioj + 1,45ez(zcts.

  Sue and Sean are havi+bi b2hvel)1lng a tug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward Sue a el2il+bv1)hbt $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F acts on the ss:dod; oya zrgb.3+iy/s aa *:tack, and it accelerates d:+aoby za dyis o/.rg3s:*a;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 48t. fp xoezyim:,(:7i p0 N stands on a scale in an elevator. What will the scale be reading when the elevator itfx ozmp ip.( yi:,:7es accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevatorngp e1ga3hwzze(i4( 7 . If the mass of the person is 60.0 kg and the elevator accelerates downward with an acceleratio n1igpzeg( wa3 hze74(n of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If the mass of the persn4( mrl3 lm0(ze5wl r3mmz/ny on is 60.0 kg and nllr 5w m4y(z (n/30rmmme3zl the elevator accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal force(gb)4 2rslg8ygpki *m s act on a 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The sec(k yp284*rgl) gismbg ond force toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flae6d.wihhi fj f3-)ty.x ng/-ztbed 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 stop)ft- fjy- z/hgd .6hi3wexni.ping distance 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 held in pla5n r ,*fdd9ouzgn7hl.ce by metal brackets that can .hnl9n 7o* gddur,5fzexert 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 the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg f*6hunu-wzpb ;ag2j4d 3uuzt1hz 7 f(and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass 4a;u7*h6jgpu2n wzbt u-z1fz3 (uhdfof the pulley.)

  In the Atwood machine shown in Fig. 4-1q -01nlvcjfc,h1qfq.4oll9 t2bu hh1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the massj-.214vq 1nu9 hfh1l0 bqcfl,lt ch oq of the pulley.)

  A student pulls a box of books on a smooth horizontal fls*dx (im tl( s+gc98 sh7*-t-wuvhudloor with a force of 100 N in a direcu-7w vs(s(mc *+lshhd tlxtd g*u 8-i9tion 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 force (r8uovt h;*3j wxi.zo /ktq l5jrd/0dof 100 N in a dio/(jol0h.; tq/r8z*iruvwdt k 5x3 d jrection 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 ropezuach0z ) v75,e3iqdas as shown in Fig. 4-2. What are the tensions 3)c0, v zzd7ai 5uqhaein the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of l.vbxp;v6d; 7qd: e zcthe traffic light?x;v6.pdlq7ecv : z;b d

  Two boxes of masses m and 2m are in contact with each other btc-f;dpj dz3qc 2.7 ion a frictionless surface. (See Fig. 4-3.) What pq c2db-di.c3zj ;7tfis the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each ofb7x c elc/wni,kdop0. *4 t(uther on a frictionless surface. (See Fig. 4-3.) Wht., ulwdx op4ib*0c ec7/f(knat is the net force on the more massive box?

  Two boxes of masses m and 2m are connected bypydqz, hop)-6 a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the connecting op-y ,zp6d qh)rope?

  Two boxes of masses m awy9vht(guzm ru-4 bh46s) 9fznd 2m are connected by a rope. (See Fig. 4-4.) If the forward-z uzs(ft4vb4h9h69r mu)ywg force on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a k ae(e0 mw,fl:cord running over a pulley as shown in Fig. 4-5. Box a,:emw(kel0 f 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 static and 4ag nok jw+(okd1(,nckinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is adoj a w+nck(n(o14k, gpplied to the box?

  The coefficients of sta 8ln-yv*dg/j1noq+ e ltic and kinetic frictions for plastic on wood are 0.50 and 0.gl n v+jynqld1-*e8/o40,
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 dirm,fird9+3 in5 *lzbc rection. It slows and comes to a stop wi *ldn3c ,+irzbm9 5rfith 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 isk2zr k+zjz7(4tqm*, iwvi+ yj l-h i,i pulled by a 5.0-N force. A 3.0-N friction force reyj-z i hl2itzmiwr 4,+*kj,qk+z7i( v tards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N acce w9r2kgx1k8fpp+zg 4zsf ;e *mlerates 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 1bi /qcn*bce63ngi .i *0 m/s. It slides 50 m on the ice befb qcice*b/in6.* i3ngore it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accv9ycr-k ud+v 0ident, police find skid marks 90.0 m long. They determine the coefficient oc9 ruk+-dv0yvf 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*r xjqejdf--*w :. daq. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the-jrf*j*-qxd d e:aq. w 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 r;k6vo5i 2 ea4)gqx,chmf 4xy 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 massive box, wh4r e 5,acqh2g)om6fxv4;ky i xat is the coefficient of static friction between the boxes?

  An object is on a frictionless t4vk0kq .qz s5inclined plane. The plane is inclined at an angle oz q 0ks4q5.tvkf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill m.ll 4db;j2mu 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 annr2b;s 3:if v--t btn;w/ iym0fpp7ug 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 a lk) e/r7fp0nn pqej85n 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 vev /b8j3/7dtfrxx no ia/a kz/fl ji-*+locity of jz/ r*av7iffajx/3ndkl- 8i b/ + ox/t6.0 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 downauj6 ,vl m6ci21ajb; j 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)pp obt lxb.lsc30wijs)le.)x 37 8cg 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 weigaqy um,yet ;85hing 500 N along a rough surface. The cable attached to the log makes an angle5 qyt ,8meu;ay 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 on a roup;enswy2km /0*xd;e*sc+ recv( r ,qsgh inclined plane tilted at an angle ,*;qc/n p c mr;*ev drkw(xe +0sssy2eof $33.5^{\circ}$ 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 grg21:ji u n 2kpoql*1ccp,3a mkstuay(.d)i2z adually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction betweenzyk munu q l:o). *p1i3a2ac22c(,s1jgdik pt the object and the plane?