Which of Newton's laws best explaipna c z*h;8e85r;nc9llq5q d tns why motorists should buckle-up?

  When you sit on a ch g r48:nfgnnw1d 1la h/w4gsu-air, the resultant force on you is

  In the absence of an external force, a mo bz2q0/;ci yeqtil n:2ving object will

  When the rocket engines on the starship NO-PAIN-NO-GAINwa 3uu8 isgkz7-5t -xm are suddenly turned off, whila zitux-wm 3gs 8ku-57e traveling in empty space, the starship will

  A rocket moves through empty space in a straight linl;*b vv h- ;xhafz1t14,drc:xw3d mkmr hd)w3e with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applie1)z d: vx3mb k w dr3hdftm4,wxcvh1r-h* a;;ld to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forwae( + jun*i(l2hvzi kihvu4u,0rd, and you suddenly fall forward. You can imply from thin j0i(ui(iv*hl4 ,h u2ue+kvzs that the bus's

  You are standing in a moving bus, facing forward, and ti6m s vqh7p;+you suddenly fall forward as the bus comes to an immediate stop. What force caused you ptms67qi; v+h to fall forward?

  A constant net force acts on an object. De jn;2msm )uu9oscribe the motion of the object.

  The acceleration of an object is inverselym-m,wwge+i/i he2 3z y proportional to

  A net force F acceleratesib-j8xy 6 ,rcx a mass m with an acceleration a. If the same net force is applied rx6 j,c-ib y8xto mass 2m, then the acceleration will be

  A net force F acts on a massam6bs7w g;6ggsj5.6p ws 7ocf m and produces an acceleration a. What acceleration results gjw6 b75og6 ;cp. a6 smgwfs7sif a net force 2F acts on mass 4m?

  If you blow up a balloon, exsh 4i.lo 6u5s ( jp:rpsn5ffo 2in60and then release it, the balloon will fly away. This is an illus nip r 566:elp5.sf2sh0suji( fxoo4 ntration of

  Two cars collide head-on. Atu 1rrm.8zj cd)(k5u ,qagy e3l 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 car exerts on the first. This is an example a,rem zlc8yd guu (jk3)5.r1qof

  If you exert a force F on an object, the force which the obj*byll* jz 7xfo85rv .pect exerts on you willl7b8yx*l .5f z pov*jr

  Action-reaction forcesz*oaluwx/bl ( ow87c4 :if; wk

  Action-reaction forces arjjl:1cl,s r i0c e79em7mwu e fs nr94l4f3o*re

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage 15ro .m e;q+ ooxaxh5kto the car. Since a lot o1xkemq h5ox ;.oar+5of damage is done on the car

  An object of mass m sits on a fljq)/3-7fgxvooi o+k p+btop bv :i8)rat table. The Earth pulls on this object with force mg, which we will call the action fogoxb q+bovrpikp7f+/io8)- j3: )vt orce. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a strin*fp- pfsmx-h ;cvm n.1g. The Earth pulls downward on the toy with its n.c -v;pxh f1-f*mspmweight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. The 0aqcm hrp*sf5a2g ) ln,5sb(i ball hits the bat with an instantaneous force, whosei0,hrfbs25pa (l5cmg an *s)q magnitude is

State Newton's three lac2maqhm(n+ee dlk*(0 iw,7lfws.

  Mass and weight

  The acceleration due to gravity is lower on tdp0jbol.wgh, f wq 0uxtn2 p8b7.)b,uhe Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, comparepb0, )hb7ftod. w2luxun8p.,q wgj0b d to Earth?

  An example of a force which acts atqd kwvx3 kv x904pzl8s+kb 9uhjy63d5 a distance is

  Who has a greater wei(4jc--aln7wes f f(t aght to mass ratio, a person weighing 400 N or a person weighwscja-nl-afe( ( f74t ing 600 N?

  A stone is thrown straight up. At the top of3 l1e0gn5n:m lb7;q 4rw nomoy its path, the net force acting on it inb4lgylm:mo 5ewqn7n ;0r o 31s

  A 20-N weight and a 5.0-N weight are dropped simultan/ u/l;h9tafx deously from the same height. Ignore air resistance. Compare thef/;alhux9 /td ir accelerations.

  A brick and a feather fall to thq g fn(-ppzx3:ulqf.(/iuk7oe earth at their respective terminal velocities. Which object experienkq l7u f:zqunpi(o(/gf x-p3. ces the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling ofnmis(ox :0 gg, an elevator. The elevator is moving up at constant speed. , 0s:(noxmigg What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elevatotivj-- bo ,.ed;ze tga 5)lbc+4;vbtjr. The elevator is moving upward, but slowing down. Whab.,+leec4iv gb5a;db) ;t-z jjtv ot -t is the tension in the string?

  The force that keeps yfq m gcwr-9 r b -w6,t4)h6;nfrx)lkujou from sliding on an icy sidewalk is

  It's more difficult to start71nj tkax p0e+ moving a heavy carton from rest than it is to keep pushing it with co 7ne at1kp+0jxnstant velocity, because

  A horizontal force accelerates a box fp 3v/ogt*r+nc rom rest across a horizontal surface (friction is presenv3 /r*gtcp n+ot) 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. Thus we 4nvrcf 66g9 nude.ff5 n +eds*no2)rccan .+ofersn26vc6 rfnud4f n9d 5cg)ne* deduce that

  A block of mass M slidzp sx0jdsc6(v:i2y6 ves down a frictionless plane inclined at an angle q with the horizontal. T 0v z 6:icxj6d2ps(yvshe normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angl y,k47ntdcb r56bqqw 6ddf/lm;, k q/be q with the horizontal. The normal reaction force exerted by the plane on the blo7bw/ k,fqb;,4/6n c rtybd 6kddqlq5mck is directed

  A block of mass M slides down a f7o8:zn b: i t9xnldl2krictionless plane inclined at an angle q with the horizontal. The gravitatiolz7t id8ln b9n:o :k2xnal force is directed

  Two toy cars (16 kg ag(,f*p kul)vmote(4 nnd 2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement pn) ,(mgult4(e k v*ofwhich best describes their acceleration after being released.

  An object sits on a frictionlesu 6lwz;o;5rg. h;nv gss surface. A 16-N force is applied to the object, and it acch 5;g.z;su6vwo g;rlnelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg e+53vn d ztxi;; b7blpcan accelerate from rest to 27 m/s in 7.0 s. What is the average forwabpti lbz+;35;ex v n7drd force on the car?

  Starting from rest, a 4.0-kg boi/vmx l*c 0s-wiu1v*c 4b c6xddy reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on the bol x*1v c ixvu/0c6wcsm4* d-bidy?

  An antitank weapon fires a 3.00-kg rocket which acquir+hi,s)ph gsm-v n*8mdo 3anmw y*8ba*) +atlnes a speed of 50.0 m/s after trhntm8m8p msgw d)*o)ni*3 sy*lhva- ,+a abn+aveling
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 mass from fj 5abfnx0vzu q -e3dqxy5.2.re53 xve52 qb .fd-xnuz.jayqf0 st,

  What is the mass of a person who,22ih-rgq)gn hqcu z: weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surf,e0osflp6nt 7qgt i/u:.ee :n dl9)fvace of the Earth where the acceleratio: n oe)qutp0:n7.gvef6lf9s/e,t lid n 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 objec1xcbtyr/h kt3s3b /x2 t on the surface of the Moon where the acceleration due to gravity 3t /kx/3b hs y21tbxrcis only 1/6 of that on the Earth?

  Object A weighs 40 N on Eart-esjj ord8l 3oo,m c97kez6+ uha0z 2oh, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the massesoleo3mkz2a j6-o0+hcz o du8r ejs7 ,9 of the objects.

  Sue and Sean are havc)y 4t d,xvq6ting a tug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N foc6)vxtytd4 q,rce. 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 s4 yg djz 3d9cn/5;qw*(znrfifrictionless surface. A force F acts on the stack, jds/z(y;cfzrgn4 3wn*9q id 5and 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 scale in an elevatev fbap41z5b 2grok9u)y4;jkor. What will the scale b91 o vr 4jebp4k y;z)5b2fukgae reading when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If thez l r v6g7 gx27nr4y-ni3ddg.e mass of the person is 60.0 kg and the elevator accelerates downward with an acceleration dzv g6-r37ge24 rlidxg. n7ynof $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. qaus2t zed b3li1ndr8b :;9:c If the mass of the person is 60.0 kg and the elevator accel9r2bi18tbad;s:u lq n 3e: cdzerates 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. Onkmjs3c/ bt 5mq/c28i0 kwm, vze force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnit0mw zq2ckmi5t8bvk, m //jsc3ude 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 held in placegc6 yni.ugr cd c,xb*wsi*(5suv6;:y by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, 6y5 *cigcbxwg, d(i s6c.nvury us:;* 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 th/ br;cbq m.1b a0dws.ce 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 trav1c rm.sb. 0dbw a/qc;beling 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 and m = 0.40 kg, what is6n uud47w9bs g the magnitude of the acceleration of the system? (Ignore frictionn9uwubdgs 647 and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg an 3 lr78bikc7ivd m = 0.40 kg, what is the 7c8ii3 7 lvbrktension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of 05 xdnab 5j0,za -0t9m cm9sids pa:cx100 N in a direction of mi , x9 9t0a5na aspjs d0c:-dcx5b0zm$37^{\circ}$ 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 book-o9c djjbf3;k s on a smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the bo;j9fdc3b -j kooks is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 1u1jirw75 s1p3z cpe5n00 N is supported by two ropes as shown in Fig. 4-2. What are the tpupcz55j e3nr17 w1siensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mri 6vno65uxssc 5y7i3ass of the traf3 y5nsi76i5c6uxov srfic light?

  Two boxes of masses m andaxzt- c8-p5b 9wgk g b4m+k(dv9(p sir 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more massive bo5gmks-x9bab tgkzpv48(dr pcw+i-(9 x?

  Two boxes of masses )u 6 dzr1(/2yz jf 0uqnzk3byim and 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the mor3zybq 1)z (u i/n6 u0zjy2dkfre massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. lbf7m*:fvee6:wb3 xeom4lw ih 2 *+ wk4-4.) If the forward force on the more massive box is F, what is the om wbee xvi7lhlff 2 :+:6* 3wkbmew4*tension in the connecting rope?

  Two boxes of masses m and 2m a1 *yoyhd3.eckwpie9 i )p,b0are connected by a rope. (See Fig. 4-4.) If the forward force on the more massivep9ce,*oai1ke 3 d 0w)h py.yib box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running 8mqf11cik,w,tak6nr /y7j zrsj-zf 12dpr k/ over a pulley as shown in Fig. 4-5. Bo nm, 8 qrktks72dzjkcrw/p1 j-f y6/ zfa1r1,ix 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 betwe msigk2aj,8zw. i)-a een a 3.0-kg box and a desk are 0.40 and 0.30, respectively.em2,ja w ga.) -kii8zs 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 frictiopwkxmjc9*k;:zlr* j3 ns for plastic on wood are 0.50 and 0.40j:9pzk j;mw c*3*x rlk,
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 surfac4/p:c fqk7n xye in the +x direction. It slows and comes to a stop with a constan 7pqc/4:yfnkx t 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 byz1;c63+zkaol e:5 qvo te+csurface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of the objectoceb zc:y1lazt6+qe5ov ;3+k?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from resttffg,v/ v8wv 3, 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 osu)3r usoyc8d7gjm -1f 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient o)c 1s8j 7ym-3g udorusf kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks 90.0 m lu6zr+5 ;hb ptmn 5jilnnl7g(5ong. They determine the coefz;ntju5+ l bhn5g7lmnr ip56(ficient 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 afh ra;ya w10ohv6,p) and 3m are stacked. (See Fig. 4-6.) The surface between tv6prf hy)aoa;1aw h, 0he 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, 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 surzg b:i(m 1kio,face between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less, km oizg(ib:1 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 planez/ ,i,yqj (2p2k5jmisaq n fx+. The plane is inclined at an angl ia2,mqnpxqijkjsf+/y,z 5 (2e of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flathtke+2n .fd7 .)5ro71bnpo ll2f xd*erw4hwb 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 ai56 fh+ enelu:n 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 sm 8hdh5qr4;y9 llehalac(d8 g(ooth inclined 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 apa;m6xq 8. yp 6iusii0zt:.ko constant velocity of 6.zma tii.i80sy x6q:uop6.; pk0 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 dow;( -e2b.srjd:uvtow yn 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 ncat8irz r9/* 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 along a rough surfacowp3a18vzs2gtl9 - voe. The cable attached to the l81z3v9 gst-wovp 2alo og 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 tilted at an angle+ u f yrk4/ldx-/dnc-(hrq l6f-l /r d4/fkurc+6-( fdy lqhxn of $33.5^{\circ}$ 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 lwo w5y1j 6;lmqoo0uzftw 6kr4 ek:,1angle of incline is gradually increased until the object begins to slide. The0y o1w:ktjw4m5k,lo1;q6o f lzuew6 r angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?