Which of Newton's laws best explainsb)5 km5;klt xv cy)zf6 why motorists should buckle-up?

  When you sit on a chaii7l1ihp7p2b bumx )u2r, the resultant force on you is

  In the absence of an externa jx:9iml c9w0al force, a moving object will

  When the rocket engineruehz 20dp0io, i07y ps on the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the starship wi0r puh,d0 eo0i2 z7piyll

  A rocket moves through empkfymjy41 -xylq /w 8,bty space in a straight 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 i4q jf-yym/ x8k,1wybln order to sustain its motion is

  You are standing in a moving bus, facing forward, w/(4x oiy:jy qero1i0hk0 iy4and you suddenly fall forward. You can imply from this that the buqj:h0 ekii (4yyi ox10wo4y /rs's

  You are standing in a moving bus, facing forward, and you suddenly fallq a*ofhehhxy. rv.w 633t8uh1 forward as the bus comes to an immediate stop. What force caused you to.*tah. yhxeq rho f38w3vu6h1 fall forward?

  A constant net force acts on acs1btfl6g59z7nl th( n object. Describe the motion of the object.

  The acceleration of an object is inversely proportional tooe6 rn*c)+77 ah4pfkpyl+ba p

  A net force F accelerates a mass m with an acceleration a. If the same net fo*z)1 a8qom7*ro drfbad, pt9a rce is applied to masfd*pqro a9 7, )*1romd 8bzaats 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. Whpq oa6/-kp 7twapp1*ty 7j3zmat acceleration results i jzap1qw 77oatk pt-p*y63mp/f a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon wilmi443 lz5r xkzl fly away. This is an illustratio4kxm3l ziz 45rn of

  Two cars collide head-on. At every moment during the collision, the ms0:rh(q :,mc1vam1a/ jxaasgagnitude of the forces,a0m:vh a /gsa r:1x1 qm(jac the first car exerts on the second is exactly equal to the magnitude of the force the second car exerts on the first. This is an example of

  If you exert a force :xbvc g/ 6dr3dnucsh u)0(izfj.e*)o F on an object, the force which the object exerts on you wil/(r v)d)ces 3buig.h:x *df6j 0onuzc l

  Action-reaction forclzj:ue 18x d3b9 b/lures

  Action-reaction forces(c(oie5z*aedzq y ;t + are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to zqt-.lh6-hzan onc5* the car. Since a lot of d hntq -z5*h cal-z.on6amage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on 0bb3q skyw c. hl.a.u,this object with force mg, which we will ca3hqab.0u w s.,b .lyckll the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Earth pz3ebekn*ua,g7 tlxn f+/ j9f e7c.kd:ulls downward on the toy with its weight force of 8.0 N. If thik :n d9*efakl,3tjzuf7 xeg7b/n.ec + s is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you withnxaw19)v wig 1ov p8i2 a 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose magnign vwo)x1a98w2 v1i pitude is

State Newton's three/ro ;uib;fo l*9r bex6 laws.

  Mass and weight

  The acceleration due to v94 oayu28a9h u 3gm5bagbo8dgravity is lower on the Moon than on Earth. Which of the following is true about thgvub g2h9u m5o9yd84a oaab38e mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force whi tv(rx.9k9fy ke0+jwjp+ jk(uch acts at a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a pers/y t(tx1 4ze,yt owi8ron weighrt4xweot /z,t1(yyi8 ing 600 N?

  A stone is thrown straight up. At tb iviu kec.p5k m7d5)nr5j7:mhe top of its path, the net force acting on b7jm.ui 7e5) inrm5:v pcdk5kit is

  A 20-N weight and a 5.0-N weigh6xaqas(z9s*k5d 7mn st are dropped simultaneously from the same height. Ignore air resistance. Compare*s aa6s 759kqns(x mdz their accelerations.

  A brick and a feather fall to the earth at the776xmeie(8fw : uwrc ub9f+x yir respective terminal velocities. Which object experiences the greater force of air f9wweuy e6xu+ f7f7r: im(8cx briction?

  An object of mass m is hanging o vo(5cpnvazg, (v +ldgfmp 70jq9.9aby a string from the ceiling of an elevator. The elevator is moving up at constant spee( (g7agajn9lqvo5,v0p+ z. p9od cmv fd. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiqk f tc a8e(:mb1fi)0hling of an elevator. The elevator is moving upward, but slowing down. What is te8t1 chf:qai0) (bf kmhe tension in the string?

  The force that keeps you from slidik9qzckfv p,kc m8d89,ng on an icy sidewalk is

  It's more difficult to start moving a(5nzdb hw z (rs*sop+dpzci3,)n iy58 heavy carton from rest than it is to keep pushing it with constanz y(c po+bws5,zdrn8s5inzi * )ph3(dt velocity, because

  A horizontal force accelerates a box from rest acrvsbgh ; / y1wi3ix9b,si9wlh 0oss a horizontal surface (friction whi9s1xs,b hwibv0/g liy 93 ;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 acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thom2gt1 bka9r3 us we can dekaor1 9b 2m3tgduce that

  A block of mass M slides down a frictionless plane incl..3ov fr )mzwaiz w9++p: 7bkm,yiwb wj4d b0jined at an angle q with the horizontal. The normal reactij. vo+ w,pw)a. r mii 34j7d+ zyb09wfmkbzwb:on force exerted by the plane on the block is

  A block of mass M sli, -csgi5ic* u qe9ugvn-dw5:udes down a frictionless plane inclined at an angle q with th q,uu 5u5wggi*d e:vnsi9c -c-e horizontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane in0c q5bkk h,f(qb/ow3 yclined at an angle q with the hbw3k,yhb/50 qof( k cqorizontal. The gravitational force is directed

  Two toy cars (16 kg andq/fej rcj q8)* 2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement whichj j* f)e/qcrq8 best describes their acceleration after being released.

  An object sits on a frw 44(*ppi )owkuyoqt:ictionless surface. A 16-N force is applied to the object, and it acceleratpqu4(*top 4y) w:owi kes at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can acgu vmxt*9lu0 g47 /i3/2g ahi ydvfej3celerate from rest to 27 m/s in 7.0 s. What is the average forw vyfj7/guimli3*gea vh20 u/4dxgt 9 3ard force on the car?

  Starting from rest, a 4.o 3q+/+:eocw1cyk oyx5 asv7 s0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on the body? 1o35sxyv/ q e7 csk+oaw+:yoc

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 m/s afte;rf4xwg m4s eea);5 der traveliera ;s5 g4ed w)m;4xefng
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 maset9)q spg) i bm(tyhg2,m 8o1os with the same force that you push a 10-kg mass from resp h8eggy9 m)2to1 m(t,s)obiqt,

  What is the mass of a person who weighs+;r) xfh r4fx.2kfiwxy- :fme 110 lb?

  What is the mass of an object that wei21ip j*qp o51wrfsy5bm0r9 p mghs 250 N on the surface of the Earth where the acceleration dqp5 pif1p1o0mm5b2 rrj syw *9ue to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of t*p:zv4br+ kp mtk,pip- 2z 6ea)rel/phe object on the s-rk4: ,6*2zz/pmree ptbkv+) ppi al purface of the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N7:kd7 x eoi5fm on Earth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. C7f57i: d oexkmompare the masses of the objects.

  Sue and Sean are having a tug-d:vzl0y+k5n;tf zer .lgt1 o-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 accelerat+k;:lz0tt erl. v5n1yf- z gdoes toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless sul+z j6 f/6k,lq fwhy)trface. A force F acts on the stack, and 6yw/j 6zh tf+lkl,qf)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 a scaa4li: 8r-z yj-k; a u5yvv)dojfa 31zale in an elevator. What will the scale be reading when the elevata-y85a3vz-1 )fduilja r z joy ;akv:4or is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an ele/cb,a ):vrqnd )gt4c fvator. If the mass of the person is 60.0 kg and the elevatoncdftra c)4 :,) bqv/gr 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 :uo:ttjtk0xb0 za6 2nis 60.0 kg and the elevator accelerates upward with an acceleratiot 2utb:o6 t0nazk0 x:jn of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. Oneaxm l5 fmnt7f *9:u3iqno9c8i force has a magnitude of 8.0 N and is directed due north. Tho n*q9t8u ilf3m5c:9n7 fmaixe 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 rests on the flatbed of a truck. It is hel:-;rhzf3u gdlvr 0-tt+ chqv,d 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 vh rq:tr0zgh;+v3-d- ,c ul tfminimum 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 truck. It is held in x; +nptai.ji3 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 toi+ ;.3n jxpita slide forward into the cab?

  In the Atwood machine shown in Fig. 4uzgpb5ia9 h8/ -1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore frigu/ bz5i8 p9ahction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.4fwx96q +eegepp(vg)7 gjkt, *0 kg, what is the tension in the string? (Ignore friction ane)+ (q97 wge *p6tjge,g pvxfkd the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a forch8; ppwe 2twyj,s k7p4e of 100 N in a direction ;,pew27kwp4sty 8j ph 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 fo dl1cn/o hh:8dga,e9irce of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40.0 kg, what 9 lin/g:,de1h coah8dis the normal force on the box?

  A traffic light of weight 100 N )fk. g9b 8txfndf 6k/his supported by two ropes as shown in Fig. 4-2. What are the tensions in the r8/dfkg6bhn.f9xf )kt opes?

  In Fig. 4-2, if the tensionsx0id 46inhf q0zqv*-q in the ropes are 50 N, what is the mass of the traffic light?46qh0 *xn0q qif d-ivz

  Two boxes of masses m and ch0ck 29 iyo+*8 iygfc2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more cg8cfyoh+ i0ci y9k2*massive box?

  Two boxes of masses m and 2m are rp yrvrw meyfd7x, 6i,3u83x6in contact with each other on a frictionless surface. (Sexy8irrm6ev 6,7w u3,fr3ypx d e Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m areag-n y u 6(7yp y bvux,ipfb0v7:tb2(g connected by a rope. (See Fig. 4-4.) If the forward force on 0g -i, 2p: ytuavbnu(pby6v7 x7gb yf(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 f f ) y5t5rlr9wns fh3g.pnj,pt84 tjxe6rs2 f1orward force on the more massive box is F, what is the acceler98j124ryxspn. ftfw,5 5t penjg3 ltf)hrs r6ation of the less massive box?

Two boxes are connected by a cord runnfg.d f.36fk hning over a pulley as shown in Fig. 4-5. Box I o6gfkfn3h .d.f f 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 9pd/ dicxt;4ys1qp64efu m 4 nkinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the 41mfi4yqd ;np pe4uc/9st6 dxbox when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions -jj7;fpw lq)xfor plastic on wood are 0.50 and 0j;l ) w-p7fjqx.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 com imv kak y6vn.z u2+pif3t.x1,es to a stop with a constant acceleration of -v. af1 x,i3+t6 kvikymz2p.un$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a j w:dnr*7v6g nfzn+i8horizontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motio8n :76+wgfj r *ndizvnn. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, fro1mc -qvd(r4ivc0 pht;5rg n7 dm 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 anac o0 s*tj:s2bf4fzma0y+ / given an initial speed of 10 m/s. It slides 50 m on the ice befor0 bza2o*ftjfsm:40n/ a a ycs+e it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid ma vlb,s)3k m/sorks 90.0 m long. The k3b,sl)msv/o y determine the coefficient 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 stackedk: n)m* .)avl)r .rf8 lobyz;qui s,oj. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface betw ,rolsz*ifl:nqm).;)a. y bk) u ro8jveen 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.) Tp+4f-cm nd(li( q5txwhe surface between the more massive box and thcptlq m4xif(w+ -5(nde 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 coefficient of static friction between the boxes?

  An object is on a frictionlk- xus*s1dj.sgw065x6gqx5epr hk 5i ess inclined plane. The plane is inclined at an angle ofd5px5e*ih-5 rqw6x 61kks.uxs 0sg gj $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle y.o(gl;oaq hhs+r+0 gof $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth ievgbu (;wo22;t m+dfr nclined 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 inclined ,;lbs. rbe1pc na w4lchs;1x. 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 constanwgd,**1 li9wqk;ple tvz *pb; -b w)ylt velocity of 6.0 m/yqiw* bwp-*wltz;) pbe;k 1dl, gv*9ls.
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a mass4h)m dt irrg:9 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 dlpcoiq0 f* 6j73z*jeqto+ d+kown 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 roughk3p)s8 pmg)fp surface. The cable attachep3))gk 8fspp md 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 from rest on a rough inclined plane tiltedvt dnz +*x. 6cug(+bof at an angle of xtocd.+ gu* nf 6v+z(b$33.5^{\circ}$ 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 gray (/w(cuumwj;o9x0a lz:j :g cdually increased until the object begins to slide. The angle at which this occurs is q. Wh9juco am(w: 0zuxyw( j;/gl: cat is the coefficient of static friction between the object and the plane?