Which of Newton's laws best explains w5l a0z r1fgo.shy motorists should buckle-up?

  When you sit on a chair, the resultant forc7xq:bna -re6 b3m+ c f+b+xyyme on you is

  In the absence of an91gte do3+.aabip3e d external force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned offt lk x8w7 i)hmofmoon*8 (6f4r, while traveling in empty space, t of8lt)fhom*7m8 xo6(nkiwr 4he starship will

  A rocket moves through empty space in a straight line with mpq:j 7 9uzqx9.;p)gh +wekznconstant 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 su9q; p7wq 9h)ekz+m.:xpjz nugstain its motion is

  You are standing in a moving bus,n mh+7-npdvy 3 xu-*nh facing forward, and you suddenly fall forward. You can imply from this that the bus'n +7 n3px*n-vy-mdhuh s

  You are standing in a moving bush1tzq e -c7k yh a*ae)46ap+oz, facing forward, and you suddenly fall forward as the bus comes to an immediate eazc aa1k*6t)+e7 p yo4-hq zhstop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objt y f1d*lqo*wo)+v,yx ect.

  The acceleration of an object is inverselog*t mksv8i 8-q: lk3al zcx/;y)-u xky proportional to

  A net force F accelerates a mass m with an ahk xbb,n+qxi 5a yum7o* py0nk:-y:3wcceleration a. If the same net force hu o :-k05mxw3+b,qi*n:xpyan7b yy kis applied to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceler 7e5hqbyuz6j9(t ls/s -knl .pation a. What acceleration results if a net forcey zsjsleu /75 btkqpl9n6h- (. 2F acts on mass 4m?

  If you blow up a balloon6bhn6ekh+tyr 36l0w n, and then release it, the balloon will fly away. This is an illut+ w66h r6y en0b3hnklstration of

  Two cars collide head-+s9k l6htc7s gon. At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force the second carhg 7tkc 6s+sl9 exerts on the first. This is an example of

  If you exert a force F on an object, the force which the object exerts on you wi2jf :yd5yhap( llyy a( 5p2:dfhj

  Action-reaction forcesjoa.o d,3c ny,ut0*ut

  Action-reaction forcer 5x8pm o/xfffu7gwz6 5qkc3q0 .f.kvs are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage 5 inrndv;4s,t to the car. Since a lot of damags 5,ntvi;rnd 4e is done on the car

  An object of mass m sits on a flat table. ae;ou)9fd 0sj The Earth pulls on this object with force mg, which we;uf)e0ojs9 d a will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Earth pulosc0n bdnf8bmx9qqve (;-* 0; 4qbazbls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "r;mq4bba0 o-e(q; sq zf9b8nxvc*bn0d eaction force"?

  Your bat hits the balx wsd-jg,1 qp)l pitched to you with a 1500-N instantaneous force. The ball hits the bat with an instantanx gs )1j,d-pqweous force, whose magnitude is

State Newton's three laner5; 3nar loisai/94ws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon tule2.rbxlus f8j3 5dn3xw,k9 han on Earth. Which of the following is true about the mass al l n.w2j,xux5 b89s3 kd3urfend weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distanczk k))frnu0 6zejh2e 7e is

  Who has a greater weight to m++id(l9g m jfyr/cap-ass ratio, a person weighing 400 N or a person weighing 600 N?/ i-yl a+jfrg(mc p+d9

  A stone is thrown straight up. At the hl b(dx;xnf sh( j.2f3 iana5,top of its path, the net force acting on it l xx5n;h.(hdj fnf,3(isba2ais

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same heighvn,*)ctbk *ka1 x s;mct. Ignore air resistance. Compartk*;a 1mn)*cs,kxv bce their accelerations.

  A brick and a feather fall to the earth at their respective termkr h,ro((y c;iinal velocities. r(yh,ri(c;o k Which object experiences the greater force of air friction?

  An object of mass m is 4- jlltd,9ni+8 bxp okhanging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is thek 8-j tobnxdi9ll,4+ p tension in the string?

  An object of mass m is han tve gu(nco r7yis:2:3yxj 8h/ging by a string from the ceiling of an elevator. The elevator is moving uptsj7nve:ur 8y/:cy 2iog3( xhward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy7ck4w3xi;:h pcbxf 5e sidewalk is

  It's more difficult to start moving a heah 4.l/k wlh;1w qffpzq;:oy6avy carton from rest than it is to keep puf.6klw1h;zh /lw; q4yo:paf qshing it with constant velocity, because

  A horizontal force accelerates a box from rest acroqtsq )-mk)szbqkz/2r7 gvr .a1n (xh1ss 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 horizo) kxv- tz(q/anbsh qgsmrr)2 .k zq117ntal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thri,7mj+:r(wyk1e tpnhaau fn5. a/d ;us we can deduce tha ,h+rtrjyef(:nn;a/715m a.da ikpuwt

  A block of mass M slides down a frictionlesu2z3znh5 c( pzs plane inclined at an angle q with the horizontalz n53c2uzhz (p. The normal reaction force exerted by the plane on the block is

  A block of mass M slidiln r0:6hhlul)q:wa --p/f ryes down a frictionless plane inclined at an angle q with the horizontal. T-u/:w)lfh:6anh l0ily-prq r he normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless py /g 8m6jvik9y95n: ndqnpjn.lane inclined at an angle q with the horizontal. The gravitational forc6m:yvn9yd /pi 8ngn5qk.jn9je is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on 1yp.3qh6 gy(jfkx ki, an inclined plane that makes an angle of 30e with the horizontal. Make a st .khkpgxf,6qjy1yi3 (atement which best describes their acceleration after being released.

  An object sits on a frictionlbf9*e-fup r0+thvt3 k,vd g:ness surface. A 16-N force is applied to the object, an ,bfd* +pgfteuvrn3hv 09-t:kd 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 to 27 m/st 3;7tpconb9m zwi,j8 in 7.0 s. What is the averag9bom t8; 7pcizwt3n, je forward force on the car?

  Starting from rest, a 4h lh0/c:je),)nwby ed yl9rd080isa h .0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net forcejw)sya0d0 b0h hlyr/e) 9e,ild:8c hn acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 5m. as u- -ccbiiu7qi/:0.0 m/s after t.amuii:c-- 7qsu/bic raveling
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 massyvwtvj25 mez 9gs7y16/av4ggth0 .v l from res 0g lzt25e749a h6ys/1.vwgv tgjmv vyt,

  What is the mass of a person who we;m vjgn9omqbh, 8j,a*,lx/ rsi.i+ e bighs 110 lb?

  What is the mass of an object th j3b ol6f-cn.iat weighs 250 N on the surface of the Earth where the.lc -ojbfn3i 6 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 objelhx* .rh -vb,hct on the surface of the Moon where the acceleration due to gravity is only 1/6r-v xhb, *.lhh of that on the Earth?

  Object A weighs 40 N on Earth, and object B weidvm w. mvn.,a5ghs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of v .avd., nmw5mthe objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of at8 zw gilujzs(r0q*ka:j / +z: 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope acca /*zrk0:gzjw jsz8lq:( +uit elerates toward Sue at $2.0 \; m/s^2$?

  A stack of books restsc r 1fd22xra mq9la(k- on a level frictionless surface. A force F acts on the s(2rarqxc9m-ka12fl dtack, 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 stands on 4wa epo a.*3uvop0 rd/q5jp:ua scale in an elevator. What will the scale be reading when the elevator is accelerating downwar:oj0e.4u rop uadwp53q /*apvd at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass ordsf,rm.:nkk -3r6 (:gkih(8ibcrsqn: jc6r f the person is 60.0 kg and the elevatoiscrr rkg(ihc- 3:kq.j6, 8(bsd:rf6n:kn mr r 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 the mass of the person is 60.0 kg z0dtt xzcj06mf au2 (o(k:l3 iand the elevator accelerates upward with a03 jlct(i (0zaot6ukf2zmdx: n acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on e sx)hkb /iv1;a 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second;/ k1)exhsvb i 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 flatbed of a truck. It is2iuxk.y4w, al l* z(eg held in place by metal brackets that can exert a l.y ulexk,w zi2 *4g(amaximum 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 of a tru )hkz5x5;1 sspyqs0 ahi;4h iuck. 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 to slide forward into the) suzy 1iaskh0p54 hi5xs;;h q cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, wh9vn 4*uwz0. pn o+lsgkat is the magnitude of the acceleration of the system? (Ignore frictionzp9.*gk+v n0 o nuls4w and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, ijv 8iv56ye31 t me3vb);irqdff M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore frictioibvv 31 ve3yf tjed);iq586m rn and the mass of the pulley.)

  A student pulls a box of books on a sef7noo+hti l u18u:0s mooth horizontal floor with a force of 100 N in a directiot7fo :su o18nuli0e+hn 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 smoo/ ;xqp)nk6rba7nw p6ith horizontal floor with a force of 100 N in a direction/w76brin q; kp6xn a)p 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 , of o,. wegl3s0amfjvk7 mn3-by two ropes as shown in Fig. 4-2. fm,o svwk-3 ,.7l gn 3jaefmo0What are the tensions in the ropes?

  In Fig. 4-2, if the tensioy1gnj( +twx/ qpej n8-ns in the ropes are 50 N, what is the mass of the traffic lngw/y(8p jn jx-+e 1tqight?

  Two boxes of masses m and 2m are in contj bq 4jij9c:-qt)l4w sact with each other on a frictionless surface. (See Fig. 4-3.) What is the accej qi: 49 tbj)4wlsqj-cleration of the more massive box?

  Two boxes of masses m and 2m ar*wdp;s74pgs. a.z m jxe in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force o4d *jz;sa..wx mpp7 gsn the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If ru6 .qmjqpgt( +rk-x4 the forward forc(+rjprut-6q.xkq4 m ge on the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If the x0o tk4w (v4rvforward force on the more massive box is F, what is the acceleratioox4( v w04rtkvn of the less massive box?

Two boxes are connected by a co;7xlro9u34q0ev h gfurd running over a pulley as shown in Fig. 4-5. Box g3u7lhr 0xe 4;ovfqu 9I 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 kinetic fez z y+ok81vr3rictions 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 applied to the boxzk8rv 1eozy+ 3?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50 m:i40lier t*i and 0ltii:r 4im 0e*.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 theg y i34wkk1c1. qml7ob +x direction. It slows and comes to a stop wiy1bw.4l 7kqg3ic okm 1th 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 n2p9 n*rax;ypm- cw4i surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceley m2-4nwc 9inx*p rpa;ration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at a rate of fgx6nim orq9 2rz k223 )5b+tj9rxr lt$0.50 \; m/s^2$ 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. It slides tep48; y/f+pgqacrc k 9r +j4n(omnx(50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck a;( (c n / kynm4x4fa8prctg+p9r+ ejqond the ice?

  During the investigation of a traffic accident, police find skid marks bblkhaj f *dni s;3kky5(/+l 0l.kvs990.0 m long. They determine the cobv3; kkn *sa 9hs5.yblk/difk(+l 0jlefficient of 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. (See Fig. 4-6.b+9. y/pswibm p om 9g60lwgx/) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. x/69.smmi9g0bp yb+ /gpo w wlIf 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 and9f 6-xuo,hhkc p;/ci i 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 lik cxch/ph,fiu9o;6 -ess 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 frictionless inclined f8wu 1 .o:sjbhplane. The plane is inclined at an angle of o.hb1 8:swufj$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an ro4q,qrwot92 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 planef blju4hd zn28g6 ql)4mjtu,4 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.7rxd:cz5t;jb 9 rxu q 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 di n .y stt1t2za7ltxq 82d2;mrxrectly down an inclined plane, at a constant velocity of 6s7d81qn2xa zyltt; r.tm22xt .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 s y3n6.dosyksrz263 uklides 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 -xc .)nv n7mvgm slides 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 alongl:p on8jl(un(h)nj h r5 oqs,3 a rough surface. The cable attached to tp 5n3j: 8rjuo ,hl) (ln(hoqsnhe 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 from rest on a rough inclined planekn5now hea:*5zhena0d /qw27 tilted at an angle ok zh0/w :h e*o5dewn5nq2n a7af $33.5^{\circ}$ 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 oaojb,**jbvddufe af/,j9w-. n an inclined plane. The angle of incline is gradually increased unffew*ou, -bvdj , *a.jb9ja /dtil the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?