Which of Newton's laws best explains why motoristv;s0 c*/r a oy+gg ,lbz-;bvcos should buckle-up?

  When you sit on a chair, the resultant foil (to+rg( fpk14ro,, :fxgg arce on you is

  In the absence of an external force, a moving ow u9.h+rio.iblg 3-y qbject will

  When the rocket engines on tyz 8+iu,vgki)he starship NO-PAIN-NO-GAIN are suddenly turned off, whilei+k) gyi zu8,v traveling in empty space, the starship will

  A rocket moves through empty space in a straight l .l9.:a fmkkr.ffl-s oine with constant speed. It is far from the gravitational effect of any star or plaso9r. lam.f.f lf: -kknet. 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, facing forward, an8t 9n ttrctn)1d you suddenly fall forward. You can imply from t trttct8 )nn19his that the bus's

  You are standing in a moving bus, facing forward, aiejjag0u:0 8j nd you suddenly fall forward as the bus comes to an immediate 0:jujie0ag j8stop. What force caused you to fall forward?

  A constant net force acts on an zkmni (dk b.mp n+2b8 q7xw9:ne*qbtyx9f *a/object. Describe the motion of the object.

  The acceleration of an object is inversely propoeoq5w- e*ouku pzm6 28rtional to

  A net force F accelerates a mass m with an acceleration:.cw6aw9q hl a a. If the same net force is applied to mass 2m, then the accelw.qlhwc :a9 6aeration will be

  A net force F acts otzvko) r61,cj n a mass m and produces an acceleration a. What acceleration results if a net force 2F acts on mass ,16z rotc)k vj4m?

  If you blow up a balloon, al lsl ,15v;6m xo4ckfdnd then release it, the balloon will fly away. This is an illustrat64oscldfk1 l ,lxm5v; ion of

  Two cars collide head-on. At 76en k .25hpjxqml lb/every moment during the collision, the magnitude of the force the first car h/5ql2ex lk 7.bn jpm6exerts 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 F on an ob 8pj 3h-5vwhusject, the force which the object exerts on you will3w h uhvsp8-5j

  Action-reaction forcvp +qo5h+tdvq3 hm+3 nvho a::d-b1sa es

  Action-reaction forces9p 53-w/rnq h0d2 vvx zh;erbm are

  A 20-ton truck collides with a 11f/gvybm6uq )500-lb car and causes a lot of damage to the car. Since a lot of damage is d1g )uvmy6qf b/one on the car

  An object of mass m sits on a flat table. The Earl (um,p/aqj rlxroaeom2z-hq5;d 9+/th pulls on this object with force mg, which we will call the actior pa-9z (+ daoq2 uqe5;rxmmh,l ojl//n force. What is the reaction force?

  A child's toy is sus1s-xq x im :wm;vnm n)c;8vw00n yzc+wpended from the ceiling by means of a string. The Earth pulls downward on the toyi:wxvvmc8wc0zn)q w yx1 ;m0s +m;nn- with its weight 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 *z:r iix8z28d*i,a: cy sezmjforce. The ball hits the izc :2: m ardx8e8szi zy*i*j,bat with an instantaneous force, whose magnitude is

State Newton's three qai 9p)lzgj, -laws.

  Mass and weight

  The acceleration due to gravity is lower on thh7 m ci6 i,h8fdwk.g5ugtq-6w1l0uy ve Moon than on Earth. Which of the following is true about the mass and weight of an astroc tu iku ,5gh 6dwgyf-liw10h .7mv6q8naut on the Moon's surface, compared to Earth?

  An example of a force whpfoyd l24 (;jjich acts at a distance is

  Who has a greater weight to mass ratio, a pe8q yw ga6yka3 :0,zr/tzv-qwzrson weighing 400 N or a person weighing yaa 38w-z:6z/t0yw zqqr,kvg600 N?

  A stone is thrown straight up. At thxhg13q ly 65fle top of its path, the net force acting on itly 5fglq1xh63 is

  A 20-N weight and a 5.0-N wei,x+nd+6-tnwi v i kz4qrf 0 +9kwtajor2y+c1ight are dropped simultaneously from the same height. Ignotkwiiwv4nc -2 a+ fr6 +xz9 jk,+irdoy 0n+tq1re air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal velocitie , 0y gz5lgo9dt91ykics. Which object experiences the great0cgtil951y ,dg9 kzyoer force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. The o+h e9jzgv4o229x qst elevator is moving up at constant speed. What is the te+tog4 9zvqx22ehosj9 nsion in the string?

  An object of mass m is hanging by e6 gsc1vm1wp,1m *vnga string from the ceiling of an elevator. The elevator is moving upward, butmgcnv6 p1w, egs*1 mv1 slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icfid) ;w bh r8f4en-kw2y sidewalk is

  It's more difficult to start moving a he7zh g ce ,):cws oe:gkh*-axz;avy carton from rest than it is to keep pushing it witwceg ,zhsozk *:: a-); 7hegcxh constant velocity, because

  A horizontal force accelerates a box from rest across a horic5exa3,.: hseexyey4zontal surface (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 happens to thcehs .x3:eyy4x ae5,e e box's acceleration?

  A packing crate slides down an inclined7*jtrm yjhx k;.+sxk by0eo z0;xolw+31t ,t t ramp at constant velocity. Thus we can d ,xo;x3zjtt1jlk7ystbh+*mk 0+ty0e.r w x;oeduce that

  A block of mass M slides down a friction.m v/qb h.pms55gnz5hless plane inclined at an angle q with the horizontal. The nor. hp/v5s55m h mzqn.gbmal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless p-na9/ rycozi+taxi 2r+rb/c.r m pu/9lane inclined at an angle q with the horizontal. The normal reaction force exerted by the pl+mc aa rx/rrb-/c 9zop2 9u. yrti/i+nane on the block is directed

  A block of mass M slpi 8xo40 qcjb 9t7g:zcides down a frictionless plane inclined at an angle q with the horizontal. The gravitational force8:o7g 4 t cbcz9ijqx0p is directed

  Two toy cars (16 kg and 2.0 kg) are released simulv3k3sk2 v e;yc a4g/k(p j1x /xqmqo0ptaneously on an inclined plane that makes ane;p/2qv q4gayj0s 3p1kc 3(v/m xkkox angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied to tzooekl8z721 kcg0.qq m+d 4u +p0 zzy f2piy)jhe object, and it accelerl2+go4e2yzm)8 pz 7fz +pdc.0 uyi0kjzq1oq kates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from r:4yb roley2: eest to 27 m/s in 7.0 s. What is the average forward force on the:er:2b y4y oel car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 53kgblf/2j zvf(aj5g m/s in 2.0 s. What is the net force acting on the z l(bv3j2j5f/ kfa gg5body?

  An antitank weapon fires azbwpu+-o) 8x6dc(heb 3.00-kg rocket which acquires a speed of 50.0 m/s afteb-ubh wp o 8ez(cx+d)6r 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 mass from re(b81vlk 0 e,j3vpzaux st,uv(81a3 ejpk,blzx 0v

  What is the mass of a peojr w2fx1,1)3oxwe* lgx eq;hrson who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Earth wduk-l.fy ) :elhere the accelera.key dlu)f-l:tion 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 object on /ctsz(;2y/0 ,oz/zw cv /k,v3 tvymkjvj8ewl the surface of the Moon where the acckvz,vc o slzvj0m/2 c3tj;kve8 /ww/yz ,ty/(eleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N :et*nzw-s 8k(l 6n.jt2easgwon the Moon. The Moon's gtkjnwsg(t sae6.-z 8w:*enl 2ravity is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite,ukv7/w9u eg5(j(n zl r8r iie ends of a 5.0-kg rope. Sue pulls with a 15-N force. n7rkwir,5 ugz(e/vi8e j (l 9uWhat is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F acts on 1jghiy6s(2,bz65 vorrg / gam the s 2 ,zg(yjsvhr5 m6/1o6riag gbtack, 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 stapg svxqq x*)0ck)r8 e-nds on a scale in an elevator. What will the scale be readi r0ve-)*x s8g)pqxc kqng when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the ):myfwo9 7 xzxhz..ed+95p nok u.imd person is 60.0 kg and the elevator accelerates downward witozm 9hdo +zm5 d:7f9unk.p)i x. x.yewh an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides pqadv:x abj;jg.); n whufq 1 kh(++:oin an elevator. If the mass of the person is 60.0 kg and the pgn;va jfbk jxa)dq q:+o.+hwu:1( h ;elevator 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 ma 5xv7:yxu dty(g*3/ endqi0if) uc)vy ss. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is the acc fxdi uqcg n/*7v:05u) ydxeyi3 tv(y)eleration of the mass?

  An object of mass 60008fd-oz2 q:93 yxykwqb kg rests on the 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 traveling 15 m/s, what is the minimum stopping distance if the load is not to slide forward into the caybq- 3:koyzx2 w fd9q8b?

  An object of mass 600 pyvi1.1xv*1q t fdcdp.*e. ix0 kg rests on the flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the tr xfi1e1c. q1*ppv*i xd ytd.v.uck 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, *ldz6xbu,.p p if M = 0.60 kg and m = 0.40 kg, what is the magnitude dub p6l,.px*zof the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown inx*dn:rl: wio5c5x d f, Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore frictdid:*:, xc5x5l wr fnoion and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of 100 4kqs d3arsm13N in a directios43k 1 dsraq3mn 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 zj:db8 kw , hr;(kw1yabooks 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 books is 40.0 kg, what is ywh,j: 8bz1r;wa kdk( the normal force on the box?

  A traffic light of weight 100 N is su 6e(ud1z7p9 dre8tst zeden n4,yj7 p4pported by two ropes as shown in Fig. 4-2. What are the tensionse,re4ez (n7d 67 pt9tsdue1jp znd8y4 in the ropes?

  In Fig. 4-2, if the tensions in the ropes;;wae dh/s n7y are 50 N, what is the mass of the traffic light?hna; ;eyswd/7

  Two boxes of masses m and 2m.9oye+ lrotvec k47wx n l2u/- are in contact with each other on a frictionless surface. (See Fig. 4-3.ote/ v rc4 y29kx wo-en+u.ll7) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each 9 ;rztkfacd.5))wy vdother on a frictionless surface. (See Fig. 4-3.) What is the net force );5w) zt dfa9vyrck d.on the more massive box?

  Two boxes of masses m and 2m are connected by a ropkrs :oj ndd wk,41(3lvoq..xee. (See Fig. 4-4.) If the forward force on the more massive box is F, what :lo3,neqrswj (4okdd .k1 v. xis the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a ro sdphnkw:lc-v io4 tmn,(d7, 5pe. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the les5c md7lnhkv, ndo4w s(: ,-ipts massive box?

Two boxes are connected by a cord running over a pulley as shown in Fi 5ch h7wnl3kg2z x1j:mg. 4-5. Bocwj 1ln7km gx35 2zh:hx 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 kinetioh d4p:z83ve 3n zivm25ys6iuc frictions between a 3.0-kg box and a desk aroh dzp328y4ns6viev 3i5mu:z e 0.40 and 0.30, respectively. 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 frictions for y7-c0 s z+d3z tt4zicyplastic on wood are 0.50 and 0.40,d s40i7c-tc+zyy 3zzt
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 comes to +( (- jwwtzgn:fmrxx,a stop with a constant a: gw-(n jfx+rxm(wz ,tcceleration 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 su k:x*gxg lxjjv6+ev8 ,rface is pulled by a 5.0-N force. A 3.0-N friction force retards the mxk,6v: 8* xjvjlg gex+otion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a ) g.5-mnlk2)5kuf qjpueyt7v 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,cb(c f7q u 1w, 9dr2m/r(yczkc a puck is given an initial speed of 10 m/s. It slides 50 m on the ice /2r7 wqcm9y ,fk1cub(zd crc( before it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigatioejht .)j: v,tjn of a traffic accident, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevaili tj t.:e,hv)jjng 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.) The surface betwjb0g qwn4z9:, qz3jfkeen the more massive box and the horizontal surf4f3 q qzngj,:zb w9jk0ace 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.)h5nx;w4i5 -adu tvpb) 4 6rktt 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, what is the coefv axd4t 6-h5b ;t4iu5r)pkt nwficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The planvr qeg stvy 8,p9e/i )j5y8r5ue is inclined at an angle ofsgv5,)rptyq8/ yv9 58 reiuej $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an anl:e5izp7;n , el e1yxvgle 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 angle ocv+of gd)p u+6f, afx4f $37^{\circ}$ 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 smooth5j/ ,1- bnkztj,dzfn i 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 e *wa+7d in yhi(9k9y4ga 8ue,xj(oupplane, at a constant velocity of 6.0 m/s.(awd9ay n9p,ykoe i7 x+ e(4 iu8u*jgh
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 rougfj3kz:na.e ,j h $37^{\circ}$ 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 dow nfqneo/ ,r;j1n 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. The cabwa k(o bhv/ o:d)1hyl5le attached to the log makes a(k/davl :who) y o1hb5n 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 release-a)fxh3vc kr;d from rest on a rough inclined plane tilted at an angle h3ax)r;-kfvc 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 angle of inc6arv/zas3gj,lbt-0m; iz-h+f x)fk alma; 1kline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the objec +h ;f60a) kg-smaj 1afr;b,t mz-xlkazi/ lv3t and the plane?