Which of Newton's laws best explains why motorists should buck,h pr/7bkh row0+ ti +z9wgogp6s+t)dle-up?

  When you sit on a chair, the rw+dtj n;rp3b )u:0qnt esultant force on you is

  In the absence of an external force, w*l jx00lkn :h3 b(8f*w)uiyyyg g6ina moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned adg 5.u)wbcsu a8)w0 zirnrhn7jg9ro-f, :q *off, while traveling in emd gn7.af w 8)i0r j*gcb,q95zrar- ouh su)w:npty space, the starship will

  A rocket moves through empty space in a straight line v .2 a5:yx y/(esy+oyi tsqc,iwith constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the rocket in order /2 y st oq(y,c+ya:ivie.x 5syto sustain its motion is

  You are standing in a moving bus, facing forward, and you suz 5jy9.,oc dqm5+u +eb bfzt5mddenly fall forward. You can imply from this tha+.zqb+uje5m f 5moz 5bd,c 9tyt the bus's

  You are standing in a moving bus, facing forward, and you sud7 imllylw-7lb/,ti;ya5momnz;)5 om denly fall forward as the bus comes to an immediate stop. What force caused you to fall f m i oitm; nal5yy,o7wz-l)l ml;75m/borward?

  A constant net force acts on an object. Describe the motion of the object deddsq av;f+on6488-ph-4a hb v6pgz.

  The acceleration of k+rxz5jxo ae+v1s f(7 an object is inversely proportional to

  A net force F accelera.7cwt bsy81xh4b7uatb2uk e 4tes a mass m with an acceleration a. If the same net force is applied to mass 2m, then the acceleration willu bak bh4b4yswx7t27.tc 1u8e be

  A net force F acts on a mass m and produces an acceleration a. Whatcmah:w ur5.b) acceleration results if a net force 2a)r5:mhwu c. bF acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon wi *6a53 5g fqbm7dtmjy1o4hjfbys6jh6 s5q*mfll fly away. This is an illustra 316q5mjgfa5oyqfj s6j 56mt s*47b*ym hhbfd tion of

  Two cars collide head-on. At every moment during the collision, tksw)3.zn gjkf i*.a03 p:msnr4ye/ gihe 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 ofi30jsmk.:/.fw4is r zykg eg)3*p nna

  If you exert a force F on an object, the force which thc- n /4uoydq-he object exerts on you wih/y4q nc- du-oll

  Action-reaction forcesw96xy;1v owir( txp)9 nuc+-tzbp r4 q

  Action-reaction forces a p.iekz 6 u,ii,hyf -;anm0pgxz/w:y)re

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage 8 h(ikg7ffhd:h8 lft- to the car. Since a lot ofig8f -kh hhtf(8: d7lf damage is done on the car

  An object of mass m sits on a flat tatq:9r fo7a0p ible. The Earth pulls on this object with force mg, which we will call the actioft: 90rapqi7on force. What is the reaction force?

  A child's toy is suspended from 0 ws9geh m7-zmthe ceiling by means of a string. The Earth pulls downward on the toy 9szmw-g e0 m7hwith 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(d9u 9pbtv4 pi; *wadr-N instantaneous force. The ball hits the bat with an instantaneous forcep9;*9p( wad v duib4rt, whose magnitude is

State Newton's three lap,k:g an fys.nxg:1vqq4f il3 ,m,j: sws.

  Mass and weight

  The acceleration due to gravity is loweozmg)c80qc3 g)4 gur ar on the 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 Eart0zg4u 3) )acoq m8gcgrh?

  An example of a force which actsm,bj7e*lu9r le.f wo8 at a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a :4(m4-fnpspww lg l9mperson weigmwm 9p4glwf-l:n s p(4hing 600 N?

  A stone is thrown straight up. At the top of its path, t9(+ dl lvv4vjihe net force acting on ij +v4id9llv (vt is

  A 20-N weight and a 5.0-N weight are d2j- iet5suo yfi +ty).ropped simultaneously from the same height. Ignore air resistance. Compare thoyi5jte)u .ys2 it+f-eir accelerations.

  A brick and a feather fall to/ .w73r)vd bc )u.qew4wwfuo c the earth at their respective terminal velocities. Which object experiences thee7cuwb4 wf.) u/wo)r3 dcv q.w greater force of air friction?

  An object of mass m is hanging by ad 6(y ng; *eehmu2ovh0 string from the ceiling of an elevator. The elevator is moving up at consmy2hgo ;*e v 6n0u(edhtant speed. What is the tension in the string?

  An object of mass m is hanging by a s vhb4)ef7a* sptring from the ceiling of an elevator. The elevator is moving upward, but slowing ef)aspb * h4v7down. What is the tension in the string?

  The force that keeps you from sliding on6t6g 4lyqz otpv/8s8 g an icy sidewalk is

  It's more difficult to start moving ) atdxv+vfa7 ze3u56ha heavy carton from rest than it is to keep pushing7 v6 tav5u3d)+zhae xf it with constant velocity, because

  A horizontal force accelerates a boo2 v. .x9rz c)*lamalwx from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditionsv*)ol la9 .2mraxc.wz 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 const .snrp(:uy a5hant velocity. Thus we can de.5usa (p:nyh rduce that

  A block of mass M slides down a frictionless plane inclined at qidzvy8kw;43 an angle q with the horizontal. The normal reaction force exerted 83 ;z 4ywkvdqiby the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an anglhj / zeym*:bq-e q with the horizontal. The normal reaction force exerted by the plane on the b*zqhy mjb- e:/lock is directed

  A block of mass M slides down a l n1(kw*d:6lddc eq yyl s. o9ap;8ng3frictionless plane inclined at an angle q with the horizontal. The gravitationald8gl1:kdop ce wn93 l6da*lns(y;. yq force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaynnc bt4o t4oz0qc r-v k-4k6fyb.nc6n 0 c/s-neously on an inclined plane that makes an angle6b rct sctk 0n.ybv6n--4oyn/ k4 fczc0-q4no 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 f, 0hqo1g 9z; k2t 7,eopfzmtdsorce is applied to the object, and it az td;o0eqmg,9 1k op,7hft 2szccelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate fromg bor+ +,ih:d9yzf jutc.gip, 0m,c.e rest to 27 m/s in 7.0 s. What ircfp., cy, 9oim0 zjt+,hg +:ebd.iugs the average forward force on the car?

  Starting from rest, a 4.0-kg body reaches dg v.0i 32tdhmxd6 7ol1 *iozla speed of 8.0 m/s in 2.0 s. What is the . x m1d3t gdz6i0*l72oilvhdonet force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquivo30hgy c 3x1/ at2khbres a speed of 50.0 m/s after travecvt1y2bh hag k0o3x3 /ling
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 1 esf d9m;+frxdo0i e;:0-kg mass from rest,o;+sfi9d: f ;r dm0xee

  What is the mass of a person who weighs 110 btm+x 2c xs8.y r8kby9lb?

  What is the mass of an object that weighs 250 N on the surface of the E** tss s2b.kklrgk9q ,n4f) ctarth where the acceleration dr g*kctl)*9ns bf,q. 42kksst ue to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 *bc*xbs+wcs y54gs* bkg on the Earth. What is the mass of the object on the surface of the Moon where the acceleration du bb5sbs+*4wsycx *g *ce to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and objepxmovrw4:ty (;e *ec5ct B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of t4 mce5x v:ryet;w(o*phe objects.

  Sue and Sean are having a tug-l*0 w8gu5pm k psj4)nj(c8vpc of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if tw0 ms(c 5 p8c)u4 njkj8vlpp*ghe rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A forceborj4zsz y 7jgro)70 3 F acts on the stack, and it accey3s0zr zr ogo7b)j7 4jlerates 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 inz w3wvcl6 gc;;g8+qrisz3 1r b an elevator. What will the scale be reading when the elevator is accelerating downward scg3 ;q z8b 63wwg vzi;1lcr+rat $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60.0 kg22pmx p*tzp;i and the elevator accelerates downward with an acceleration of t*2p p2; pmxiz$4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If the mass of zr 3 ) lqtm0,k(yxjl2j x , c,;a8b)yvktlizu8the person is 60.0 kg and the elevator accelerates upward with an v8jubt)2y ( ty zx,3zxj;lr)lc,a0i, 8l q mkkacceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on axcx 1elnd kb :6yy/7a. 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second foraek .y ybn6 lc7x1/xd:ce toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on theez .c7(qftpepb05 k) l flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N.c) ql7et epbk5 fz.0p( 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 ro4q)a qvzd/l2e59n+lc up+ h w em-sq,ests on the flatbed of a truck. It is held in place by meq+q-mdnwv poe +lsc5 alqz)h4 2/e, 9utal brackets that can exert a maximum horizontal force of 9000 N. When the truck 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 = 0.60 kg and m = 0.40 kg, whnvqm4j:r7 q jxkxe8 a 8u:2n+dat is the magnitud kma:+d2uv7enxr x8jqj:qn 48 e of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg ap)vpf5v0 jg6bm gmk*k 0n/hr f+fu:a4nd m = 0.40 kg, what is the tenubm0 pr+4:gpgkajvf5hv)/ kn0 * f6fmsion in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth h i-r 44hgtqzt/)mv vs( yo*)fcorizontal floor with a force of 100 N in a stfzq*gvim4vh /ty)( )4c ro-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 horizont7v4 8wtsc4t:1p k)jhhcydj -cal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box an kc4tcwtchy174pd -:v) jshj 8d 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 ropelhr**wty;( ics as shown in Fig. 4-2. What are the tensions in the (h;rc tw* liy*ropes?

  In Fig. 4-2, if the tensions in the ropes ar);vez7wws,cp e 50 N, what is the mass of the traffic ligww ,eczs7);p vht?

  Two boxes of masses m an0isn-df7p:k 9v mhpe ;d 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.mdsfveh9 p: pn0k-i 7;) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with0z,a 4efg *df1cpq(hc9i m;qw hs*phz5-tt(o each other on a frictionless surface. (See 5(1w,aieqzsqcf-mhh fgz o hd ptp 0ct9*(*4;Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.d2) h 4k ,flci-qf6.zcttv7 ar) If the forward force , tlq7viah)f cf2 .c64-dkrzton the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are , 8hoq0t-*a vrir:gpvpkne18 connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration 1hr pvt,o 8a*n:0kqgi8vre-p of the less massive box?

Two boxes are connected by a cord runnimlzk b54ka2 ;sng over a pulley as shown in Fig. 4-5. Boxs;a 4mkbl5zk2 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 betsbfp3j:, 8fofse ym 0:ween a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the bo : 3ef,fpm8objs0syf: x when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on ;.jzz;wzj j (vn b6i0pwood are 0.50 andz.njb(w ;6z;pijvj0 z 0.40,
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 + wydgdx(w .r:vjmw 12 op.ua5*x direction. It slows and comes to a stop with a constant acceleratiod1 jmwy *wrgu2a(.x5 pov:d w.n 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. A xv wzr3u-.)fn3b) bue vm+m)n3.0-N friction force retards the motmf.b-bz)+ vw3 v)r n meu3u)xnion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass j-fskg7q z6r ( 0;geokw)l8vh, 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 pucks*su cl*t1 ut9ez :.zw is given an initial speed of 10 m/s. It slides 50 m ctlu s9*ew t:1zs.u *zon the 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 fi ncdai x,o1 hy-7g-wqc(ffzuq.o(w(* nd skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 f7xqzd-o ,((w c fw 1*qfc.og(hia-u ynor the prevailing conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3ms3vh s h 7-;enyys3 zith)4qb6 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 static friction force on the le;vys ish byhqz337-64nt)s ehss massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4x1e( z vz2x -:mat);h8ew(zlax vd) rh-6.) The surface between the more massive(re t:axhve2 8 x);-d(z ahzwl1)z vxm 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 boxes?

  An object is on a frictionless incli ntnn3x 4)k*prk) ot:oned plane. The plane is inclined at an angle )4oo)*3ktn:nktpnxr of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a 1nl3yfhi 6 ,rzflat 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 plapr+zq3i*b;(d 6o ,mm romlf f7ne 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 smoof3hwp7 ojw -0 *sqyr8lth 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 slidetm-bnn e1i.4ej/b :nts directly down an inclined plane, at a constant velocity of 6.bn/:je .4m1b ein-t tn0 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 *kj* db03v*1sod fkykcq.,ik m slides down 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 dm, igd 8 v)socr)zt,: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 surface-/j ,q+rq vm5yh1md ox. The cable attached to th-xqvhym+djr 1q /m o,5e 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 rest on a rough inclined p5u1)xd6z 9mx w kah5dhlane tilted at an angle of5w)1dda kx9 h5xumhz 6 $33.5^{\circ}$ 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 incline is graduaerx2mv, wmk3;1qq p96)sw aj illy increased until the object begins to slide. The angl;ww 1eim9pqms 6qx3,ajr2 v) ke at which this occurs is q. What is the coefficient of static friction between the object and the plane?