Which of Newton's laws best explains why motorists shouldaq; f 6dw71pt zzjcx /a 5amcg,:;dz/h buckle-up?

  When you sit on a chair, the resultanoh999rzua w00uu: xte t force on you is

  In the absence of an external force, a moving o 70v bap;mlsu8z79taa7cdk+c bject will

  When the rocket engines on the starship NO-PAIN-*js iemiss+(a lq y,mip 1(k:9: 2doarNO-GAIN are suddenly turned off, while t( :sj*mpyd(2, ms9re ska+io1ql:i airaveling in empty space, the starship will

  A rocket moves through empty space in a straight line with constant spee-w61er ;y p/-q3leycyh0ie gxd. It is far from the gravype3yg0/ xw1q;e l eichr6y- -itational effect of any star or planet. 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,y3+/y)d kc3.e4 j i. :wahzj0ow gvbtp and you suddenly fall forward. You 3w p obj.j .y04/kwy)+z3gvdca: ie thcan imply from this that the bus's

  You are standing in a moving bus, facing forward, and you sudden)udj-*9d fwhp*+6eb itky;v dly fall forward as the bus comes to an immediate stop. What force cau) h-vpyuife6*w t9 *kb +ddj;dsed you to fall forward?

  A constant net force ac4cv h uos eq(8yst90g,ts on an object. Describe the motion of the object.

  The acceleration of an object is inversely prkmzn ukne 1,b:nw8st; 5a ib7 4fsdh5(oportional to

  A net force F accelerates a mass m with 4 p)fzb*k5pk-idorw2an acceleration a. If the same net force is applied to mass 2m,kbd2-zik ) wp f5ro*4p then the acceleration will be

  A net force F acts on a mass m and prod+ovq 298ydo jduces an acceleration a. What acceleration results if a net force 2F acts on mass 8dody qov9+j 24m?

  If you blow up a ballooni+.i p (n1rhlcp 7gv(xd6d1mr, and then release it, the balloon will fly away. This is an illustration o vr1(+npx rdi7(m6i. l1gcdph f

  Two cars collide head-on. At every m cry j* bw9nc+.bgk:6doment 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. Thwcn6b*9rdyk :j g c+b.is is an example of

  If you exert a force . kza+t, 5zb18e itif;mw;yfiF on an object, the force which the object exerts on you wi;ibf 8wi1akziz ,+.5ye t ftm;ll

  Action-reaction forcesry6 b), ,nldv+tv6wprh(s 5f n

  Action-reaction forca9/h) y .gjc :ef7dlques are

  A 20-ton truck collides*c*fjb1 n0rnp with a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is donen1nr* p0* cbfj on the car

  An object of mass m sits on a flat table. The 8 e6ynn.t4fmcEarth pulls on this object with force mg, which we yfn4ce m8.n6 twill call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a str+ t, dnz3bez+/vt2thx i h:o9 vklp-(;cboll*ing. The Earth pulls downward on the toy with its weight force of 8.0 N. If this isixdt,9+h/bltck eo-; 3o*b+l:v ltnz p 2 zh(v the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N ins:jma ff1 bs18bntvhi/j*1 zv/tantaneous force. The ball hits the bat with an instantaneous force, s /1hvjb fam/1bj*1 vn:zif8twhose magnitude is

State Newton's three l c1 e bd6h-*wvtdd1o6waws.

  Mass and weight

  The acceleration due to gravity is lower on the nm2p l 2tenc5qd 7jf9qp m9l4m v,8mu*Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Ec9n 2 7mmtfemd98,q 2pum5lpn*v4jqlarth?

  An example of a force which acts at a distancew 3 fsgz 3ijrw91h6n/q is

  Who has a greater weight to mass ratio, a person weighing 400 N s+ t7gkwso vw;2(sx;o or a person weighing 60s;ww+oo;7 sks2 (tvg x0 N?

  A stone is thrown straight up. At the top of its path, thetjj4zs8b2+ oj net force acting on z 2j4jos+ jtb8it is

  A 20-N weight and a 5.0bzq7 +qkutbfdfz s)t85(+dl6-N weight are dropped simultaneously from the same height. Ignore f( bk f+ tzbusdz56qq87ld+t)air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminalw,ry+e vna7c,-5 vj mx velocities. Which object ey +cr xvv7nem, 5j-,awxperiences the greater force of air friction?

  An object of mass m is hanging by a string from the cuj.ws3 y+it1 heiling of an elevator. The elevatorhu 13.w isjt+y is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by aa1a 4 0k5iuctzu at.1k string from the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the u 40a5u1cz1a.t tiakktension in the string?

  The force that keeps you from sl 2swy0/ 4m6p.zqg,2fbps gsj,mp t;eliding on an icy sidewalk is

  It's more difficult to start moving a heavy cartopf/a:xqz*xf0 n from rest than it is to keep pushing it with constant velocif/ fp 0zqx*:axty, because

  A horizontal force accelerates hae sjbo*6z)ksv7znx22 (pd, a box from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that t xbozn27sk he ,z6sdp 2*j()avhe horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thus we cal h eit8x p 9lzx-m+t71+,lt3yv(rvxwn deduce thl8-1 xz e l7lt+9vtr(mw,3tvx pi y+xhat

  A block of mass M slides down a frictionless plane inclined at an ak87cw,hdn0 6ms) dsqk)/ wwm yngle q with the horizontal. The normal rek m6cm, 8hnds0sw)d/y)qww 7kaction force exerted by the plane on the block is

  A block of mass M slides d5kacm: xv ljs )ajd ls;glsm(2qxj;) s:3yp 8)own a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block 5 x 3l j ls:g ymad)jpsvkasm2lx8(jc;:s))q ;is directed

  A block of mass M slidfo8xi;yc5vb pv wn7py asa,3w/t q59 (es down a frictionless plane inclined at an angle q with the horizontal. The gravitational 9 x pv;8iypnw73a5tb qyos(,ca5w/vf force is directed

  Two toy cars (16 kg and 2.0 kg) are id n4ku:o7az:rt g3pl0 m-o ,jreleased simultaneously on an inclined plane that makes an angl 7 oi-zrun3 jkogla40m:t: ,dpe 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 the ovy-).u ) nswsfed6;a nbject, and it acceleratse).vadns-;6 nu )fwyes 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/s in 7.0 s. W/l1 u 7eo rng awjqpx+l8bs928hat is the averagws/ur7 e b98xp q l18janog2l+e forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. Whakys11-7r ychit .rdc8 t is the net force acting on r1csyc-yr1hk t.i7d 8 the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 aiaww qyn8 ch, .lsd32 el;xc7tf*d6.m/s afterel82* d7. f, w wcas;63xqalni yt.cdh 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 same6z;y nt(*mtf8w 7oh mz force that you push a 10-kg mass from resoyz*hn w(;8m7 t6ftmz t,

  What is the mass of a person who 9q+ mqobza+)at(/ rjy6d j py/weighs 110 lb?

  What is the mass of an object that weighs 250 N on 32t(s nyx1rx+y x2 wn z0twh1x-oar3xthe surface of the Earth where the accelerationn y0nho+zwt1y -r(xrw2xaxs x t1x233 due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. W7 zp62vxo uam6dxy130y ma(tdi ** oxbhat is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 di a1z yvx ob2td7* mmyo60p* xau3(x6of that on the Earth?

  Object A weighs 40 N on Earth, and object;/ fqfy aq/yk5* zqz1d B weighs 40 N on the Moon. The Moon's gravity is one sixdyz/ aq f;q*yf 1qzk5/th of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposi4bu0f tf sq6cf q3+ u+hvv4*zpte ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward vsqvq4ff 0 u 43ubt6ch+f p*z+Sue at $2.0 \; m/s^2$?

  A stack of books rests hgdisptu +-m 29l62/pgoma3ion a level frictionless surface. A force F acts on the stack, and 2/-a2gh 9tms3iuo6ppiml +gdit 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 eleb: v absyc7.)lvator. What will the scale be reading w7bclv a:s)yb.hen the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale r g9ep d 3yyw5 2ycvou+9ij5:gu5w f.hbides in an elevator. If the mass of the person is 60.0 kg and the v p9 .bo: yj5+9f5c ywhw idu2u35ggeyelevator 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. I+oeu .:+heygj f the mass of the person is 60.0 kg and the elevator accelerates upward +u g :heeyoj+.with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces acn w89jqm n-l,it on a 5.0-kg mass. 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 acceler-8mwiq9l n nj,ation of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in placp5y c zp2if/ok dz29iah18j9ke by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, hij/k 1zkp9 ify8a2 pozd 25c9what is the minimum stopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg 5) k(y-mxmym/d7u elerests 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 5 (lm)ukmy/eyd-7x em, 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 = 0.40uic/vx2sj,6gxi 0ljj ra/(:d kg, what is the magnitude of the acceleration of the system? /i2g,l r0ju6j(jdv/sic x xa:(Ignore friction and the mass of the pulley.)

  In the Atwood machine ss,qj nvc/qaf(j z ;+vmf0okkvn-f0- -hown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the ten-afjo qvzn nk qm/f+v(-v 0sfjkc-;,0sion 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 for ad4dr*1da(cu zwgj*. ce of 100 N in w ad 1au.4 dc(rj*d*zga direction 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 force of 100g yqe +x+9mt:v 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 thtv++:e xyq gm9e normal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown xn0u5- c8aemigpx /:v j:5r)vlbt l1q in Fig. 4-2. What are the tensions in thejlxm c/0iev: bpu58tqnv-g l)a:51xr ropes?

  In Fig. 4-2, if the tensions i/n92b wso t:escew 58vn the ropes are 50 N, what is the mass of the traffic light:2 /v85bwcw9ns otees?

  Two boxes of masses m and 2m are zs3cu7,m4;udhzf4 k+-)wvsm itagp;in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the accel kwm4gtv- )psz7,msa;h+;z4 i3fuc uderation of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a fric225mv96 e2ykky ulgittionless surfa 5utk 6y2e2iy kgvl92mce. (See Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a p7:5n5uo wkbce5z 9glrope. (See Fig. 4-4.) If the forward force on the more massive b lc e9guo5zkb75:pwn5ox is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are cofz bt1:l7 )bn8uqumof gf/c; :nnected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration /mft:z 8cu 7)f1bnlog qfb;u:of the less massive box?

Two boxes are connected by a cord runngzkry;r +j4 v1ing over a pulley as shown in Fig. 4-5. Box I of mass4rvz1j rkyg ;+
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 frimybh8*oz0; 2p/vhk4wqlcn3 h 1u1 bp actions 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 1 hzcbm21 pavyou1; hw0/l *nhk8pq3b 45 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on js ciuj-s b orpxt/;u*b .zm(.*(3bhowood are 0.50 and *x*r. uj 3mbpb-its ho(z/bc uos ;.(j0.40,
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 dih7g9z1lh+ ;xmxe0t u/r.dzc hrection. It slows and comes to a stop with a co g;0um ezhd lh1/97h z.rcx+txnstant 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 pulled by a 5.0-N force. bx/c+yu)z) lyck, rz bm9b;t) A 3.0-N friction force retards the motion. What is the acceleratio/+kbcl,z 9my xb yc)bt)rzu );n of the object?

  A horizontal force of 5.0 N z8n t +,vpn bsm3q6iu7accelerates 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 puck is given an ini8z2jc q qnfs1m-e n)p(tial speed of 10 m/s. It slides 50 m on the ice before i 2-j(p1c) qmnz8sn qeft stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid f1. ;rt(fard k/iot3j 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 prevailing conditions.;r /j f (tr1tkadif.o3 Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fypk )0 k0qi8 t..n*n bbetj8jaig. 4-6.) The surface between the more maeja*bpnt k.kij)0b0yntq8 .8ssive 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 s3obl5h52sahdn 8xj0r;j mp j /urface 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 massia23hl/ on5j5r;xj jdb0m s hp8ve box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The p. kx-p.dnp x9/vqe7ajlane is inclined at an angle /q p .pen7- 9kavjx.dxof $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle o fq j4mreqk/*8vfv+fhmv sb e c5x353o/bb-q7f $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclined plwq2:0dxel,t+7 sq3oy7a+ y zj tfy8s mane 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 smal2afv ti5j-8ooth 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 a constant velocity o,pz. s+km gk4ef e,pkz+ 4skm.g 6.0 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 roq v tfl0g0k2 hyby4.t+ugh $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m sk7dns;jrs.vndb ;t. 1y+ jz c;lides 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. The cable a c;u0frj o8fpnl7lv3 2ttached tou 32jlvr80f pcl7;of n 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 res;3zabkrw:,p 5d ud+rzt on a rough inclined plane tilted at an anglerd; ,5 kdrzzw+b3:a up 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 to0 0+jnja it*plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs +ni 0tjjo*ta0is q. What is the coefficient of static friction between the object and the plane?