Which of Newton's laws best explains why motorists( jn8hagn93 i c*hiul: should buckle-up?

  When you sit on a chair,h5* km7 v.qyvmpt1k4emg 0o( x the resultant force on you is

  In the absence of an external k*ypy o 0425c zws8xriforce, a moving object will

  When the rocket engines on the starsz9 x7bsk 5x9;3xm sdafau.jx) hip NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the a5mdxz kuxba9f7)9sx;x.j 3s starship will

  A rocket moves through empty space in a strakf lm;-vxp,y 9ight line with 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 to sustain9x- vfmly;,pk its motion is

  You are standing in a moving bus, facing forwa)zq ka um0:v:wrd, and you suddenly fall forward. You can imply from this that the busum:k )v0: wazq's

  You are standing in a moving bus, facing iz7lw vx5 n0sf xc.g/:forward, and you suddenly fall forward as the bus comei g w s/czl:fnx.x057vs to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe t )h/ k80 gg1thlqgja1the motion of the object.

  The acceleration of an objec(i.,/owoppm609fi)t l d rl pzt is inversely proportional to

  A net force F accelerates a mass m+qmuqe t*lk2(6k6nta with an acceleration a. If the same net force is applied to ntq (2kema6k+6tl *uq mass 2m, then the acceleration will be

  A net force F acts on a mass m and produce,xf6y+ 31t) d wddzw mb:qqlv16+ twwos an acceleration a. What acceleration results if a nel3qd6t: w qy6z d)w,+xfb1otmdw+vw1 t force 2F acts on mass 4m?

  If you blow up a balloon, and then rzcgt tt; 8c ,3weh2swhv2,bfpi*a2 7jelease it, the balloon will fly away. This is an i22*sjc,2ft8,t;ip 3v h wzge 7hwatb cllustration of

  Two cars collide head-on. At every mome85x;8xjghj u6lm;d/q2- a hxpa su; cxnt during the collision, the magnitude of the force the f adaxg/sx hucx;l8pu-j 6;xhj 5;8qm2irst 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 object, the force which the object exertqmdh-3 k44 n5 ib 6vrctls7s;ws on you wilc4b-r3w6ns;57s l4 tm kihqdvl

  Action-reaction forces++q,mf l b3r9gp 2;f8 b brq-yemao,/fd2 hrbo

  Action-reaction forces arereg qqe3 s0i12a;fp)c(w)fnr

  A 20-ton truck collides withlftip 1+ ne06xdjgo) : a 1500-lb car and causes a lot of damage to the car.p n)f+e x1 ig0:tldj6o Since a lot of damage is done on the car

  An object of mass m sits on a flat table. Tue3-j yt,hd e:.u) qnwhe Earth pulls on this object with force mg, which we will call the action force. What is the reaction force?n.-q:hwyju) eeu t,3d

  A child's toy is suspended from the ceiling by means ox,jxt s;+6vjhk (kpg w/n u(6bf a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is tv;ux (n,/pjtkx6g 6sw+ h(kjbhe "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneouir, 8i-e7-zr;- sxfq,t qk cwys force. The ball hits the bat wi;wef,i-- rzytrq-x8 kci, sq7 th an instantaneous force, whose magnitude is

State Newton's three lauh+ v4va/m b,tws.

  Mass and weight

  The acceleration due to gravity is loweshf2fyw4 b8 i0 fqs0;jr on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on thffw4 2 iy08bq; hjs0sfe Moon's surface, compared to Earth?

  An example of a force which acts at a dis4 th-ea4cbie3tance is

  Who has a greater weight to mass ratio, a person weighing 4.jpazfr/ 1n+ebg. c u*00 N or a person weigu1n gpb/jezc*r a +..fhing 600 N?

  A stone is thrown straight up. At the top of its path, the net force actingx yjc9w11u/wu on it 11wy /w9xcu juis

  A 20-N weight and a 5.0hc4p1r- h//n e8lqida-N weight are dropped simultaneously from the same height. Ignore air resistance. Compare their accelern-18a e4cdi/qrlhh /p ations.

  A brick and a feather fall to the earth l /8ka pvyvlf6r )y7qem5-2 lbbjlk(6at their respective terminal velocities. Which object experiences2b-l/ 57e k )vj6f mk ly(8plvl6qryba the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an *6g-d t9b;g5l9w uk eyl eamj;elevator. The elevator is moving up at consta6bme lk9d- gt 9*ug5;e;wjalynt speed. What is the tension in the string?

  An object of mass m is hanging by a str7tajy 28zm+dy ing from the ceiling of an elevator. The elevator is moving upwart+2j8zmay7 dyd, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy 2q i t1*-n*umzv fw0iysidewalk is

  It's more difficult to st:x- 3v0ip5vx) :exmm1e lpgj5qon8wtart moving a heavy carton from rest than it is to keep pushing it with conseq5n)0gv5:p3e xjxmtvl m8x w oi-p1:tant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (fn rev8m +a35xubz; kq3riction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception th3+v 5n3bq;zue kar x8mat 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 canntr i(f z5xtckn i4z+86*kdb5 deduce5knz*ib5in 4 +ft dc(xt6kz8 r that

  A block of mass M slides down h5 x8yhvl x;r.a frictionless plane inclined at an angle q with the horizontal. The normal reaction h5x.hlv y 8;xrforce exerted by the plane on the block is

  A block of mass M slidpv*/n aniddmw, 07lhdek2/bh9) y9ho es down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on t/v9nd2p0/7dl *amkh wd9yin o )hbhe,he block is directed

  A block of mass M slides ddblz m 3qpuzh q4eb7vjd 3+11-own a frictionless plane inclined at an angle q with the horizont -3 zpvqelu1bdb 1hd3+zmqj74al. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneouslfze7g b7 xctzjwp ed8l ( n;sw0 6ikuj8/i/(g1y on an inclined plane that makes an angle of 30e with the horizontal. Make a statement whicc(unjl( xiip j8;6gfwsz/d7kb/ e8g7zet 10wh best describes their acceleration after being released.

  An object sits on a j64v7s):exjzhcg.xu3 x7 e rn frictionless surface. A 16-N force is applied to the object, and it ae7zng:xexx)j7j c4. r3shv6 u ccelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg cz/04yvgl)p) e3cfde wan accelerate from rest to 27 m/s in 7.0 s. What is the 4f0pcg v ew/le)z)3ydaverage forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s i lfba.mq,k7 8in 2.0 s. What is the8ilf,qm7kab . net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 m/s a3 qgcy/nx.n ;xfter n3y gnxx.;qc/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 1tyyj.a.:r 2mjr 17 /t2:dc (j phwbsav0-kg mass from rest,2(t2 :.7t arbjjs1 :vajh p /mwr.ydcy

  What is the mass of a person who weighs 110 ld50u 0ydkcd 3z21 s5ttf i(uykb?

  What is the mass of an om :4qr6wixd /gbject that weighs 250 N on the surface of the Earth where the accigw/mq46r: xd eleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg o acxa x+95vwt+ dwdg c3m9*z5on the Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 o3g5cvcxam+za*wx9 9 t+ o5d dwf that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the M8n9h7) gy+nrut k* )v 3wnoifhoon. The Moon's gravity is onfh8tnnok)n3i)+79y ur* hwgv e sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 5.0-kg r,ig*j j4) c.djsy4 ;vslgn u-yopicj nd* su,ggv.-4ys4jj ly; )e. Sue pulls with a 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 fricrdxls+0ikmgllx 2z rx)q6 )30tionless surface. A force F acts on the stack, and it accelerate6 xis20)x )rlx +ql3rmkdlzg0s 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 48bd*0jrss5cr 5 ; (alsf0 N stands on a scale in an elevator. What will the scale be reading when the elevadjlr a0fcss*r5;sb( 5 tor is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person 9 8l eylrnu-6y1o h xev pdoq,-rdq0.(is 60.0 kg and the elevatop9ydrqq-o6xern yo -lu dl0. v8e(,1hr 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 -h vjd7k.u6gaperson is 60.0 kg and the elevator accelerates upward witjg-v6a h7du. kh an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg m* fjnocc 6 ncycg-c,88ass. 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 acceleration of the mafc 6-o *n,cnc cy8g8jcss?

  An object of mass 6000 kg rests on the flatbesqyx xiz9m(; r78v8l k9inim-d of a truck. It is held in place by metal brackets that l ms i(8myxkni8-7;qivx 99zrcan 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 cab?

  An object of mass 6000 kg rests on the flatbed of aw09/pgrw:j* yli stbdhc :u:3 truck. It is held in place by metal brackets that can exert a maximum horizontal forcej0 /:w: lu g yrbh*3id:9tcwsp 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,q7 (z h0uqd/wl what is the magnitude of the acceleration of the system? (Ignore friction and the mass of theqw dl/hz70(uq pulley.)

  In the Atwood machine shownse /sbu.zm5hxo+u( e z y-ri02 in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is (os hb+xr0em/ 5.uys-zue 2i zthe tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on aq f,ceyt eu/7 cxomx,b/7 l:,z smooth horizontal floor with a force of 100 cb ,t / cflo,e zy7,eumxx:q7/N in a 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 w6xk s6 i8pn8m bdn pw2dhu3:u(oe+/oa force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books3 2d8i8de/oh u (bswu6mn:okxp6n +pw is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown in Fig. 4 2se,7 wxampv1bk,wo3-2. What are the tensions in thew3m s2p xvowek 7b,,1a ropes?

  In Fig. 4-2, if the tensions in the ropes are 5lbgwix8q*qw t*o6 )v:2 ,ywgf0 N, what is the mass of the traffic l*tw8 qygqb :ox)vl gfi6* ,w2wight?

  Two boxes of masses m and 2m are iptt 9;(1 v*lngw 7rf5bgqbl 4in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of7plbq( 9 4wr5tfibnl;vg gt1* the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictmwtz odqp5:7 4ionless surface. (See Fig. 4-3.) What is the net force on the more massiv7p 5:zdm4qot we box?

  Two boxes of masses m and 2m are co uvrw 1conx1pg:2/ l;c2xw4mxnnected by a rope. (See Fig. 4-4.) If the forward force on the moc:wlx4wr2nox/mpu xcvg; 1 21re 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 /8t6hil uiivt 55gki x2cwgm)k. 5v-l Fig. 4-4.) If the forward force on the more 62v-c5g ix/mkk5ih iv)il8ltgtu5w . massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley a jli-bq 0yhlg)2)gdh*s shown in Fig. 4-5. Box I of mgdy)il-hg *2 ql)j b0hass
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 betww phy7yvt+ p)kn78-k keen 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 15 N horizontah 8yktw+ n77kppk)yv-l force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50 a 0mr 5-a0cuxpps nun*)gnkd9(nd 0.4u*-mn0p(0x5 ark d9 n)cnpgu s0,
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 thmb v1*: mdt2opvgf9fd:9xc 9he +x direction. It slows and comes to a stop w19bdmf9:2vo:d9f mvc*htx p gith 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 pulled by a 5.0-bekc0)5y xuhqa4y, 3tN force. A 3.0-N friction force retards the motion. What is the accelera yauxe) q y,3hb0t5kc4tion of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, )e:/b;bgys r jfrom 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 initip k5jasw62lk ,al speed of 10 m/s. It slides 50 m on the ice before it2jk5s,p6 wak l stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks 90.0 hg 89 nwil1ep)m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing condition8wh 9in)p 1gles. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m axnpp ,66bt 9 q18ru:yf6vektp nd 3m are stacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the s6pqp 6 vx9 uf1ptbt8: kr6y,enurface 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.) k:es22j:jl7 b3pox bkThe 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 3l2soe7b jk:2bp j k:xslide on the more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined pl ts-kwrut97/ tane. The plane is inclined at an angletr-u9ttk sw7/ of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill th fnli)y4r7vhq/w7xmn5p9c- n at 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 .z6smg:zr x 2jan 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 inclined plane tx(es i9e4t/i milted 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 d )18.)csz uqqbhnyv(p g.5vyqown an inclined plane, at a constant velocity of 6.0 mvsquz pc)nqyh(1yqv). b5 .8g /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 rough doszr );dps4w-u.*c*g i;lr p$37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m 2se o6vmwgira,fx em43:u0k+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. Thx 1ar)sn 9xmfq ual78drd9i//e cable attached to the log makix fd 7xa89ln r//1dqua)srm9es 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 t wdgn :qcy4op 5.:)9:ixk poaqm:y0otilted at an angle :)ydo:.q:omky9 x4inqpcow a 05ptg: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 in b2l0z.o48si g kv us1e.kc8 tis60gwxclined plane. The angle of incline is gradually increased 0luxstskzeg482 gco s 8k..06 iv1 wbiuntil the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?