Which of Newton's lawv mgzb3i8u js3eyx(4n4/s, e rs best explains why motorists should buckle-up?

  When you sit on a chair,dza5 jh69i+ a(z nlkz)1ixqz6 the resultant force on you is

  In the absence of an external force, a moving o1rsjms nu*+uhupyv) ( lip2ae.4)if em ,pj .+bject will

  When the rocket engines on the starship NO-PAIN-NO-GAIN ar/i/b) n8.mx am/ gobjl boh-x5e suddenly turned off, while traveling in em.g xbm) -/nb o8a/om5/jlbh xipty space, the starship will

  A rocket moves through empty smfc e4ki5(o -p(gpwqtix+7 p7pace in a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under thespi7pq- oge +wxf7p5km ((c ti4e 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, and you suddenlyru yly g+s8-k5 j34fyp fall forward. You can k+34 ug8yrslj- y 5fypimply from this that the bus's

  You are standing in a moving bus, fac(btjc./ x3xhtaw2ryz bf 2m ),ing forward, and you suddenly fall forward as the busm) x/t(c ,br2xjy.zb3a2wthf comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an ob q-dwtf6 r5ql7ject. Describe the motion of the object.

  The acceleration of an object ishg(9: m:dp3qp lgfqf. inversely proportional to

  A net force F accelerates a mass m with an acceleration an0di2 4 tb;hlg. If the same net force is applied to mass 2m, then the acceleration will bebh0 l4;2dn igt

  A net force F acts on a yc /mcztm60r6 mass m and produces an acceleration a. What acceleration resu6z60cyrmt c/m lts if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then releaseb7x5xhc y/ 8aije()vo it, the balloon will fly away. This is an (j/abo)8civh 7yxex5 illustration of

  Two cars collide head-on. At every moment during the collision, the magnitude ofb3r:gd.ttpak nz/h k+e)86wa tt*1 im t6) dhmk nzwg83t+k ab:.e/1 ittpt*arhe 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 of

  If you exert a force F on an objfso 6)d9o7jd qect, the force which the object exerts on you wiloo sd9j fq76)dl

  Action-reaction forcl qd8 g6j -dclvxp8,s-es

  Action-reaction forces atm z22zi m17hqu*i ss4/ :bznzre

  A 20-ton truck collide3 *0h/ofta jolnf r( 6rs2w5vqs with a 1500-lb car and causes a lot of damage to the car. Since a lot*vl5j f/r62stq3 (fa0oowhnr of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this obje26g4ubkw qe+uq wxb *4 9yvo1xzyl9r7ct with force q uzo7kwb 4+9quyl*y6 gxb 42x9v1rwemg, which we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by mean gdugudo:b yx.4:p 5pq6zdk2 /pm g(q,s of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reac./yudgp ,(z6p5 kqdx4:b: 2 moqudggp tion force"?

  Your bat hits the ball pitched to you with a 1500-N instantan0 /-uca9yg5n-xsrm 5:lzznz d1 c 6wveeous force. The ball hits the bat with an instantaneous force, whose magni w5ncn 1zdslrxe:az/cg ymzv-6059- u tude is

State Newton's three ldjwa 1r+*h4i; z5knd bcb1/gkaws.

  Mass and weight

  The acceleration due to gravity is lower+m4ed v1e rrz- on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon'-dem1 + rz4vres surface, compared to Earth?

  An example of a force which acts at a distanc/v ;di4d5nj4dbac ,nke is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person weigfb/a x2j;mt., g.xdw o,tevwm7 *x q2xhing 600 N?2g w.w evmta.xto xqx ,2 xjd7/b;f*m,

  A stone is thrown straight up. At the top of its path, th6f1ws*r7a xgwcqdpg)17 f;wb e net force acting on wxwd ) 1fra1w s* 77c6bfgpgq;it is

  A 20-N weight and a 5.0-N weight are dro)n/ogwqw8q e)yn8m 2t /n2c lg lu0ci:jt61aqpped simultaneously from the same height. Ignore air resistance. Compare their accelerations.ium 2g c :qw /q)g0ltnj828olae 6/)nc1wyntq

  A brick and a feather fall to the earth at their respective term *-/)l git(o-in jiwoginal velocities. Which object experiences the w--ooii)gntj(/ gl* i greater force of air friction?

  An object of mass m is hangir0xaddur)2v sb;,i a )dk7t5ilx+c1j ng by a string from the ceiling of an elevator. The elevator is moving up at constant splrij+ 7,)a2k01i vsadd)ux5 txcb;rdeed. What is the tension in the string?

  An object of mass m is hanging by a string tpx9t 67 9mrd kk/4xkpfrom the ceiling of an elevator. The elevator is moving upward, but slowing dor4p/x km697kp tx9tkd wn. What is the tension in the string?

  The force that keeps you from sliding ov v4xr(zuh0zazhc+ a 76v9ao-n6* lcen an icy sidewalk is

  It's more difficult to start moving a heav7v-clhy:q6x0 z id;hsy carton from rest than it is to keep pushing it with constant velocity, becacqdsih0 ;6-vhx: z y7luse

  A horizontal force accelerates a box from rest across a horizontal surf .co (ey7/tgcw:htzk1vxx -s*ace (friction ivzws-1 tgote.c( * x :yck7xh/s 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 constaafj)gfmr ej7r2v75h 8voe h66nt velocity. Thus we can deducmfo)787gvrj a e f6j2r h6h5eve that

  A block of mass M slides down a frictionless0 j,+teifrl k- plane inclined at an angle q with the horizontal. The normal reaction force exerted by -j, ekr+l0fitthe plane on the block is

  A block of mass M slides down a frictionless plane w-5oyd gjes6 *0rln1(qwxwr x-;4x pninclined at an angle q with the horizontal. T rw-4 w5 6ylx*jgpe0x;o 1n xdsqw(nr-he normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclin ,yt0d ira.7zcl*s dc)ed at an angle q with the horizontal.sc7icyz,0lr.* td d) a The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclined plannq :afb3 5xq6m cxi-or.vow +,e that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration 6 on,5.oxqxmvf+qiwbc -ar :3after being released.

  An object sits on a frictionless surface. A 16-N /afyi0 h b+xk873a,z6brgvx //szlwyforce is applied to the object, and it accelerates atvg/wz0 /yaxky+/z7a fblis8 ,br 63xh $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s 6f5p a 2cfy r:,axaw3fin 7.0 s. What is the average forward force on the 6rw3p5a2 f:fcxa,afy car?

  Starting from rest, a 4.0-kg body reachesx4 s;lek u7u9h0d-eys 0 ff:la a speed of 8.0 m/s in 2.0 s. What is the nesseua 9f-kh x7luy00df;4 : let force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires2 qih.e zk-zb/ a speed of 50.0 m/s after travelinbzezq. /2-hkig
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 s1fd q90h(8qwpttzx4 the same force that you push a 10-kg mass from re04tdq9txp1( hf qs 8zwst,

  What is the mass of a person who weighs 63qi-0kdy nt.vaoqj 1 110 lb?

  What is the mass of an object that weighs xi6 y-db, /2re4ujujr 250 N on the surface of the Earth where the accelerrdbjxi /- yuu6r4 j2e,ation due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earthipv6q0 e7q c8e. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of that 60ceie8pqv7q on the Earth?

  Object A weighs 40 N on Earth, and object Byskdkp,/bew 5 8gn,(.c f6mg pluwg0 z11ni ,f weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compar.kg1 wlfn 5dzipk (gm ,g6y1bcs0,en,p8fw/u e the masses of the objects.

  Sue and Sean are having a t )2 g-t5s vk3m9yo-kfqfby6jp ug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with ag5-v9y )pm b6 -ft3fq2oy skjk 15-N 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 level frictionless surface. (*;xpscl g fq* A force F acts on the s gscp*l(x;fq* tack, 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 stands on a scale in an elevator. What wilno:5)eyq p.z;aegu 2 mp1ogva6ez:5ql the scale be reading when the ;qng65v aap1eo ezqup)2y5om::e g z.elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60.sqlwvbjs7xp yl+ z:+8d(o0n 00 kg and:v +swz70(d ljp8o l ynxsqb0+ the elevator 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 is 60.0 k9d)xr0lp vt 0mg and the elevator accelerates upward with a d9)vp0x0rtmln acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. ;038+ui oj.xbf 1e06jjwfm g9hs ubw eOne force has a magnitude of 8.0 N and is directed due north. The second force toward thf3w.hj j6m e w8 u1o9xeb+sug;0j 0ibfe east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the fy3 poubxlv,d1pf6(86m 8i q rjlatbed of a truck. It is held in place by metal brackets that can exert a maximum horizonv8ry,mp x3lqpd1 j( 86 oubfi6tal 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.2k,lg6fp ,jto 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 2, lp6tfk,gjo minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machinee o4wg.wzim2car1)))wc g hq7.g1kgx shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore fri2)z.ci7k4 qmw w)g)rw1ogx gca.g eh 1ction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, wz:yu spb*p/m :4uz.0 bv)o zzwhat is the tensionz0psb/wbyuvm:.z op) u :4z*z 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 i ,wckrrn epon.1/:q* 100 N in a oprqkcn 1ei*/nr,: w.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 b *c4jgnw;8fl cooks 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 andc lcnj *84w;fg the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 102f8t98ez j*n taob5k n0 N is supported by two ropes as shown in Fig. 4-2. What are the tensions in the re9o 5nzf8j a2t*8bnktopes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, (u hg /pouih*12f zyf4what is the mass of the traffic 1z hfoh*(/ui2 uf4y pglight?

  Two boxes of masses m and 2m are :e4kju a ;yhh4:+:eselbl o7pnj )sy8in contact with each other on a frictionless surface. (See Fig. 4-3.) What isk4;: :sleu:l hpbe yj )a84y7o+hes jn the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictio z+mc0r)l0zt 6 q,uuxgnless surface. (See uz0ru )m t0xglq+, c6zFig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m andpeb 7cege/ur7k1bzgo-yr6 67 2m are connected by a rope. (See Fig. 4-4.) If the fog716b kz eug76rpe/- 7beoc ryrward force on 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.) Iy-b 1zpu1fu f)f the forup y ufzb1)-f1ward force on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in Figq id6v2siz +(q. 4-5. Boxvz+62d qisi( q 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 frich0j o: 2jiosr1tions between a 3.0-kg box and a desk are hrjosi1 o:02j 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 py omqhr e4u 8w/y(a1r26vj o+plastic on wood are 0.50 and 0.40/ ver (1o6+qm aruy48w y2jpoh,
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 slo2 0(wrsrhje p.ws and comes to a st2esr0jp. rw (hop with 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 pulle n2 p357.zex3kg iqmz6+kb lvyd by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acc.+kyzxz qnp6 i gb7vkeml3235eleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, f ei8*aw3tweyd 25pjx(a*4sj:em1 ;vqy xfet6 rom 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 initial speed ouukliybwr;(v *v2:m vj)r )8jf 10 m/s. It slides 50 m on the w;ji2lu* y(uk:r8vvmj) brv)ice before 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 mi.,lw yk1 riq(-y*y oqarks 90.0 m long. They determine the coefficient of friction between the car's tires and k rl.i*- qyyy, (qoi1wthe 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 stack;*e3w8h ord;ch2g 4fl oulfj-xel 9k /ed. (See Fig. 4-6.) 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 fkolj /;erl38f ;x9 hw2 -leoc*4ghud is the static friction force on the less massive box?

  Two boxes of masses m a3)vem *e, zb tybkkexn3v7)3n :h ccp8nd 3m are stacked. (See Fig. 4-6.) 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 coefficient of static friction between the bxph3zn)e by*v cm )t3c,:k k8vb3ne7eoxes?

  An object is on a frictionless inclined plane. The plane is inclined a n(ds3 ccwf2jaz70k (at an angle osda02k aj3 c(z c7nfw(f $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that maksr)vn,s 3h8ijsa5ti 8es 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 an4gp s -xij6)/ zm.gw-eu pj2b smooth inclined 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 inc us py*z;2nbk2 .dk3xplined 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 vu-g 1 e5 2ykyxvw6-gr yvw(wkskd0h) )elocity of 6. w0uh) w r y-ex(g1kv k2kg)ysv5y6-wd0 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 row0wz-dm5at;j g cxv+ 7ugh $37^{\circ}$ 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 down a rocx5qeg 92j*. qo5ibnrknkdd .e1 .a :nugh $37^{\circ}$ 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 50a 1(wvx*z1kqz0 N along a rough surface. The cable attached to the l1(zwv 1 *kqzxaog 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 pqkjlkb 1 g9f -9 7iasc:g 6h,ea)xy(mylane tilted at an angle 1bf k ga9y a)c6-(,:hmi97yqje kgxsl 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 plan0 7d: iyhq-dpbe. The angle of incline is gradually increased until the object begins to slide. The ad0hy b iq7-:pdngle at which this occurs is q. What is the coefficient of static friction between the object and the plane?