Which of Newton's laws best explf27ju)k1o ibk ains why motorists should buckle-up?

  When you sit on a chair, the resultant force on you iv0mlps6blp 1im1bs :7h g.cz (s

  In the absence of an external force, a moving object z)kzn);*dm)f kz8 gcw51y svtwill

  When the rocket engines on the s,qawb8lfirgy/q8fcgs1 vho: l*u 8n o(17c n 7tarship NO-PAIN-NO-GAIN are suddenly turned off, while traveli(fgbw* il7 n8f: o/gay8oq,1ul c hn1 c78sqvrng in empty space, the starship will

  A rocket moves through empty space in a straight line with k:x 59u (omioao5xs5mconstant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the fo9u(xox:km55 is 5oo marce that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facingml(k4(w0faw g forward, and you suddenly fall forward. You can implgwlmaw4k ((0 fy from this that the bus's

  You are standing in a movin -;jnjc8b,t:o s1oc bw0*j bwng bus, facing forward, and you suddenly fall forward as the bus comes to anjbsj0 wcb8nc,t-o*:jno;w 1b immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objece;fv8sp/p8 a pt.

  The acceleration of an object is inversely prow *c ij )h8,nc:wb;jjx hh.swg),(j jyportional to

  A net force F accelerates a mass m with an,ac-40v lzt qljiy:f7h pd6d- acceleration a. If the same net force is applied to mass 2m, then the acceleratl4-ztphd, vfdy6- ailj 0 :7cqion will be

  A net force F acts on a ma2g3xck6t-e 7kkw z 2 m,bumd6iss m and produces an acceleration a. What acceleration results if a net fort m263e kbk7d,c6gxk2umi -zwce 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will kb, 2k6u/7; kkvet-ue hmq d3rfly away. This is an illustratio3 t7e6 b2kke u-dk/vmrhu, q;kn of

  Two cars collide head-on. At every moment during the collision, th2l 7m//,2-jkxvy ky,zbwo xjxe magnitude of the force the first car exerts on the second is exactly equal to the magnitude o xjxyxy7vkz bo,,mkj/ 2l2 /-wf the force the second car exerts on the first. This is an example of

  If you exert a force F on an vma s9hpjx:pl*96 cd+object, the force which the object exerts on you wij9d6p*+s: mh px vcal9ll

  Action-reaction forc.+fxfh zge wag ;4 v0ccqg*l)3es

  Action-reaction forces5v,8ot4o7 jufj0 iib ox,n +xr are

  A 20-ton truck collides with a 1500-lb car and causes a lot of dae 1s.8o d3lkurmage to the car. Since a olr s8ud 1.3kelot of damage is done on the car

  An object of mass m si;o y jvd8-tilhii dthi-z/-a(pi1u)p )v3 f+dts on a flat table. The Earth pulls on this object with force mg, which we will call the action for)dp)tuioz i /f-hdhi;i-i(p18-yv+lad v3jtce. What is the reaction force?

  A child's toy is suspended fro zmngp(f ovn.,h 5dtl*4 9hd/dm the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this * dnngl/h.pzv9m (odtd45hf,is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-Nlq(9 laq cfny2 ,l9*bg instantaneous force. The ball hits the bat with an instantaneous force, whose magnitude ilf*lny, 9(gq a 29bqcls

State Newton's three laws.wvq+e(*kcc. aeb4g x5

  Mass and weight

  The acceleration due to gravity is lowericmf 6+ore b51ap dk54 on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the mopb51fac re6k i+54 dMoon's surface, compared to Earth?

  An example of a force wyq9 erl3td1d(z9u ;ubhich acts at a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a p36hkv cm3 v:wderson weighing 600 wh :m 3v3d6vkcN?

  A stone is thrown straight upb(ni;rm56;4m wx gly z. At the top of its path, the net force acting on it;z6m4wn; y5im(xrlg b is

  A 20-N weight and a 5.0-N weight are dropped simultane ju6)602 i;vk to 5+bxedy,wjhz ;zuxaously from the same height. Ignore air resistance. Comparexjwzt50bo + uy6;xa;jdk) 6 zv,2huei their accelerations.

  A brick and a feather fall to the earth at their respect54fzy(qul/ a 6edz l::tnact7ive terminal velocities. Which object experiences the greater force of ai:at5e:/4ld lf ay( 6nu cqt7zzr friction?

  An object of mass m is h z t( q*-lh9o4wy*zlfkdo-z d8j3qf7banging by a string from the ceiling of an elevator. The elevator is moving up * 7yh-9zlokfjo f4d3b(lwz t8 qqd*-z at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an ele(y;ppll/p z0 nvator. The elevator is moving upward, but szy pl /0pl(pn;lowing down. What is the tension in the string?

  The force that keeps you from sliding on an iy2ht9dxsi7y dz 9m)5n;aokr4cy sidewalk is

  It's more difficult to start moving l.t i j+k;ts 0j7cd:gg-nd3ska heavy carton from rest than it is to keep pu:jdtnjg i; gt-3slkdk7s.+c0shing it with constant velocity, because

  A horizontal force accelerates a box from res1lffn 2/qx4ih,7 difrt across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exceplifnf hrfqi21 , 4/7dxtion that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an incline r/fsf:2 +v5s sc-/ynrpsag f 1nf),;vkv:putd ramp at constant velocity. Thus we can de; r+ravft:,spv/f s -yfnpsk:f5c )ng/v1s u2duce that

  A block of mass M slides down a frictivf dj: 3-i5uygonless plane inclined at an angle q with the horizontal. The normal reactvy5-3g d j:uifion force exerted by the plane on the block is

  A block of mass M slides down z/tuvy* s36xq1 g opi.m,w:bsa frictionless plane inclined at an angle q with thezg/,iw :3 pv6oquy s1t s.x*mb horizontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plancjf t1m8 /f5vt/0bqg ze inclined at an angle q with the horizontal. The gravitational force is5 0jb1z8/ mgqtt/cfvf directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclinrlz ,ul0 pj;h4.v qj3 8n-wyqbed plane that makes an angle of 30e with the hori-q q.nlj jlh; zrb0y 43p8u,vwzontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N *x/ 5emvdis2o3aqwwp*zl 3s1 force is applied to the object, and it accpsw5a*/xz l s o3 qvmw1*ied23elerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from v*wkg4jzika.(0,jxvp3 igt- rest to 27 m/s in 7.0 s. What is the average forward force on the w4 vkj*xkj 03 (.vpi,agitzg -car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What iscc5qk f,km qmbkcu60;(i2lr * the net force acting on the2( ;ckm ucli,0rkkm6* bc fqq5 body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50+tln(3ih t/cw3d0z y v.0 m/s after travel 3c+v(h wi03yzd/tltn ing
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 sam/dz; kk ykhf6(e force that you push a 10-kg mass from reydf(k6k;zh / kst,

  What is the mass of a person who weighs(+w n4raf i/)*vhxtg4be97zrf; npuu 110 lb?

  What is the mass of an object that weighs 250 N on the surface w90n)hjqvj-r4ti m n: of the Earth where the9ir-jj:4qnt n0vhw) m acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is tkno8ua .3-i)v e zas/bhe mass of the object on the surfaceuak- iso .)n8 ez3/avb of the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weig/ kc0lse0q sp 4.cfpe-ro/fh l3zx l.3hs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. xo3c fh0lezpll/c.3sr 0k/. q-es fp4 Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opl4 q ;c1b(nxkrin9a8vposite ends of a 5.0-kg rope. Sue pulls with a 15-4 n (kqrina81;bxvc9lN 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 levec ga r3tak:v4-ittrt 8yu8of9 +*e *dil frictionless surface. A force F acts on the stack, and it f o *t-tgt r*i8rai:eau+k84t3v d9y caccelerates 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 stang65ha1 +rxd3 o,zdo1 0ugydu o3pv/rw ds on a scale in an elevator. What will the scale be reading when the elevator is accelerating dgy1r d +odxr 0p3u, uz/od1oav63h g5wownward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60.zrl/ ftj8 ano7pj9 bf:2db.-z0 kg and the elevator aj28z7 -/j:baz ofr dntp. bfl9ccelerates 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 bprmqsw+(k 5 chl:;4* :xz uof60.0 kg and the elmzpcrlh :xbq w+o5 ks;f4:u(*evator 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 magnitude ofl5c.g3c)j-1rwi rxv e 8.0 N and is directed due north. The second force t v l1ig.re-c53)xcj rwoward 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 i)x 7-f0* luc6zlpvykwtofd0 pzakt /p,6lv1*s held in place by metal brackets that can exert a maximum hordw *f0v67po*0 p zxk 1lvcluk6 t,)z-taflpy/izontal 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 truck. It is held in plaghw 0erxg5)kr,cl n u*+;2 lqoce by metal brackets that can exert a maximum horizontal force of 9000 N. When the tx hq+;r 5welroggc2*)nku,0l ruck 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 9l+:msi ;n *ssxuocx8cthyf cc-l1,5= 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and y1m-8on; s5c,lcs*cci:x9xl sf+tuh the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg duy7:p j g15oc:jm2yyand m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of j:5jc2yy7d p: you1 mgthe pulley.)

  A student pulls a box of books onoaol u*9rng;.ckm;0/qe 0au 9gjb h/y a smooth horizontal floor with a force of 100 N in a direction of 9okynb g l/. *9jhguam ;ucr/e ;q0o0a$37^{\circ}$ 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 ek8ih35,cevg hz kx-c39cfou:a :dpxc j)k21of books on a smooth horizontal floor with a force of 100 N in a directio3zkovu cg5 ihk32 k,fex-p caejc xh:18dc9:)n 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 sh +g8o+c5u2cyb)8cx q t.,wxa jwrufj 9 y*j7ypown in Fig. 4-2. What are thetjwc5uy9 8 g8f* yjuxxac.wqc+br,7p+yj)2o tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of the tk+ qe *e9msfgpvoiu )q.7ai4 +raffi+qoif peski am*e4.v+g)qu 79c light?

  Two boxes of masses m and 2m are in contact lexl0x 6uk; kq3 j7fo*with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleratio lqko06;fu3 elxx7jk *n of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictcudvx/ y*x7 3x.vaqq )ionless surface. (See Fig. 4-3.) What is thx3 .q/du)xxvy7av*cq e net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) ed-0qnwpu fvc4f( 2 7b If the forward force on the more massive box is F, what is the tension in the connectinwef0vn-2df bp (q4u 7cg rope?

  Two boxes of masses m and 2m are1tir l2k sr1vz 9huh33 connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the 9 ks2hlrt1i1v rz33uhless massive box?

Two boxes are connected by a cord running over a puss z r,q:7wcg.c ya,6olley as shown in Fig. 4-5. Box c7:arqozgy.s,s 6wc ,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 kinetic frictions between a 4wieix*/l7t:hj ( p pc3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the b:7wec pihjl4t /*px( iox when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastb+ 2 w6fqysot9ic on wood are 0.50 and 0.40,yf9bs oq6wt+2
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 slow qk74ep u(+aebs and comes to a stop wbk(qp e 47aeu+ith 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 is 7zz 4;l cwrp1 1em6laxtx6k.upulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of 1;xex azw tlz16rkcl6 p.u4m7the object?

  A horizontal force ofz qywf ,;m3rc7 5.0 N accelerates 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 puct8t -ozhb9v3lk is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kine8-z b3 vo9thlttic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid mark5kytm9y2wlrlw yf; 9fu:3+gr; x v1px s 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. Estimate the speed of the car when the brx 3y l5k;mw1gf2vfu99:ypl;xr tyrw+ akes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-ypk;r0nm.uz ed, ook(:hb59j 6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the lesobrkk o nj,0;(u 5eymhp:.dz9 s 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 4 s it:aafysap t+ u :1ku+9kql,c/ig5;juhy+are stacked. (See Fig. 4-6.) The surface between the more massive blfpu/hk+a +: gas9:+j1,q ku4;t5tsu ayy iciox 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 coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. *b espf2dc j ho71i1/j The plane is inclined at an angle of jfj7 s11*dbph/ec o 2i$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flas0xo6hfn 4 1-p+gipyr t 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 plane with an anglowc h44es be4c k7,n otmw:1n)e 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 tilthdjj g h h6hvc)e:4ioy36)g/0tl1dnw ed 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 +3(zxi:u, wykiv4bcx g v .d5xan inclined plane, at a constant velocity of g3 w4 xb.i zuciky ,v(x:d+vx56.0 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 down a rou+v dxb3ijj 4o:gh $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m slidexa-emj;9aa,h 3s ev;hs 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. Thy+ iabi +axepi/tn xl2/7/g7de cable attached to the lona2e+xlgiy /i i+7 bd/p 7x/atg 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 planeii5+hep - l rjy:-,grf tilted at an angle of, heplgi iy-:jr-5f+ r $33.5^{\circ}$ 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 /nz741fuke sp incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of n7/ fupse1z4 kstatic friction between the object and the plane?