Which of Newton's lawi+dfk0 f2)idgs best explains why motorists should buckle-up?

  When you sit on a chair, the resultan.d.a2nl y hg.ot force on you is

  In the absence of an external force, a movir :l+wm)q/buui/n/w*k 6 djj(scn(cmng object will

  When the rocket engines on t6jhod(bd 1p f6he starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the starship wi1bd 66johp fd(ll

  A rocket moves through empty space in a straight line with n0i:cfg1 ,07qba e-mqw*yimh 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 sustain its motion ey00 1-bfhiin,*q:w q7 mag mcis

  You are standing in a moving bus, facing forward, and you suddenly )bbwl txk/m)5fall forward. You canlm b5 /wtxb)k) imply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddeuu.ll6 viy n-os(tp7e ( sd.h0bz;3tanly fall forward as the bus comes to an i bo(se-tu l(7v.s0zhd p6;ilut.na3 ymmediate stop. What force caused you to fall forward?

  A constant net force acke.ivm4ad/ 2b rkt2a0nk3mb 2quo -zx y7ht8( ts on an object. Describe the motion of the object.

  The acceleration of an object isxh0 a10b l 7kxlnpr(g* inversely proportional to

  A net force F acceleratsl/ tk,s8 plxoc:l.*hes a mass m with an acceleration a. If the same net force is applied to mass 2m, then the accelerati*olh/ s,t8: llkcspx .on will be

  A net force F acts on a mashp//9ye s*ct / sjz v1ul--gkgs m and produces an acceleration a. What acceleration results if h g//1 9se/vp-ujtgl-zs*ykc a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fls 5tzt( 6w +-ulrrctr2mph,8o6h dij7 y away. This is an illustrati58m2ittrt 6drp6 +z ,-l w(ush 7johrcon of

  Two cars collide head-on. At every moment during the collision, the magnitude ofu( r/o8uhd2pd5whwd/5 ua/c j the force the first car exerts ow/ (hau 5j/uc82/d du pd5whron 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 exerts on you3lpm+ nwxf 7i*tn:jk 6 wil:lnwt nxk*3pjif7 +6m l

  Action-reaction forcelp4n 13 ;lrwqss

  Action-reaction forces 6f4ihq qt,-,m/ kn. y yncjdzo (n:+vzare

  A 20-ton truck collides with a 1500-lb car and c8wm4it .z f5bk myk2g)v.h7ot auses a lot of damage to the car. Since a lot of damaget m k4w8.hg5t2)iz 7.bovmkyf is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this obcricl rt4z ,,8 :mjsg8 -nftnfz6( k0hject with force mg, which we will call the actrn0 fgj -izn864cm, tk(rlczt:s8fh ,ion force. What is the reaction force?

  A child's toy is suspeuy32ojg28yq yad/4n gd(o+ni nded from the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0io qg/duan 2+32ony y(4gdj8y N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1e6,m yky d4qlb +v-o-g500-N instantaneous force. The ball hits the bat with an ins4g yd6+k-,e -ovml qybtantaneous force, whose magnitude is

State Newton's three laws.*v+-3xtbthb:kc d q*7lk n6 ta

  Mass and weight

  The acceleration due to gravity is lower on the Moon,d,f ;-zrl whysa) cz1 than on Earth. Which of the following is true about the mass and weight of anyz hw;cfz ),1d,rsal- astronaut on the Moon's surface, compared to Earth?

  An example of a force which actchb /q-n( ryr9cc 2vsoe: 0w6ms at a distance is

  Who has a greater weight to mass ratio, a person we(zhju)dst p6iaak i6- k(m: 8highing 400 N or a person weighing 600 Nmdpai86hs za-:k((j)ht u6k i ?

  A stone is thrown straight up. At the top of its path, t)9/ .be kr//o1am .+tzcwhjhga7of ok he net force acting on eoa akkw. mjgbh/rco/t/ f.o 9+1) 7zhit is

  A 20-N weight and a 5.0-N weight are dropped simultaneousl* ,h 9zm)zmk9n5q dokn(hd h+zy from the same height. Ignore air resistanhmknq z9h+dd(z9ok* hmn,z 5 )ce. Compare their accelerations.

  A brick and a feather fall to thf b1b.z0,0 ,hize g5x:ujwvsg e earth at their respective terminal velocities. Which obj,fw, 5vx uz:00hg ib1zbg.ej sect experiences the greater force of air friction?

  An object of mass m is h xgli q8g8u87h-+ qfeoanging by a string from the ceiling of an elevator. The elevator is mof lqh 7+-equo8g8 g8xiving up at constant speed. What is the tension in the string?

  An object of mass m is hanging b0v6h.xixj 8si1a7reg. p7tw wy a string from the ceiling of an elevator. The elevator is moving upward, but slowing1pxg8ii6 7xh wj.ae s 0r.vtw7 down. What is the tension in the string?

  The force that keeps you from sliding on an icy sidemz8woef7-5 q;9 c2pok0arrchwalk is

  It's more difficult to start moving a heavy carton from res9)e 3+ r 4yaxmimjw,stt than it is to keep pushing it with constant velocityj satme w93,i 4ym+rx), because

  A horizontal force acceleaixc,g njx)t*/l/8 4e0zz sawrates 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 the horizontal force is doubled. What happens tog/n l tz),xwz48i* aascx0 j/e the box's acceleration?

  A packing crate slides down an inclined ramp at constanf*e3p 0,ic1n hz3 cs9y8dx eowt velocity. Thus we can di 0eodnw zhc318,e*xpc3f9y seduce that

  A block of mass M slides down a frictiong j2afajzt5hn102b q/f7vwhv:bt , )s less plane inclined at an angle q with the horizontal. The normal reaction forc fh0gz,a2vb/f7sbtvq)h15w 2ta jnj: e exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angler1h8 r -qd4wu fb5x-ur q with the horiz-r8b4-ruhx1 rwdf qu 5ontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at*+qijxibw 0j)grmhc47dx5u 0 an angle q with the horizontalgrw i+075u4bdm)hjic j x0xq *. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclik h yca.lg/+gfo 7gp4-ned plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being releaohf- gg/p+ cg4a lk7.ysed.

  An object sits on a frictionless surfa )cs94oj*p vbhj3ybgd 7daf4 )ce. A 16-N force is applied to the object, and it accelera y3jf4*7dbp)ahdbo9v4 )cgjs tes 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. s chf4ify +ao2;9(fqn0 s. What is the averafyh;cfia+fqs9 n4o(2ge forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2 3qf)qv3agm ol2* bs16)m ihhy.0 s. What is 3q)) hbm 3v1glfhso6q a*i y2mthe net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed ot :g;+/vgs7cuu c)vwky2 vdz9f 50.0 m/s after travelin/vg7gcyv 2:+uv us 9zcwtd k);g
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 masvv9e): cod , wrr.hjrrq)20 sss with the same force that you push a 10-kg mass from rese0 2 .rjsw)cro)h,srv 9rdqv:t,

  What is the mass of a person who wepx v6 k*z/-/lvm (:)dlvh z.u(hcricn9y8 xufighs 110 lb?

  What is the mass of an object that weighs 250 N on the*)7rx0b )mx a: dqolgi surface of the Earth where the ac7bl* )d gr)oxm:q ax0iceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass pi kzx6,nt(-s of the object on thes6z,pk- xitn ( surface of the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Ea ew q1c2h(7dkirth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the 7hwk1i( cdq e2masses of the objects.

  Sue and Sean are having a tug-of-war by pulling - nbqf3h12ufcon opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force ifh2 q-n1fcub 3f 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 the sy t:dzk3lb c /d.c tt6+fc(7wjtack :cd7jz+3y/lcbfw td(c. tt6 k, 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 will t4go59fxut/zb5e-ele,wq, n ehe scale be5x,n5 qbo,9welg4et- f eu e/z reading 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 person is 60.xtfbfhv,q u-t: 4w*53jq5yx p 0 kg and bj 5:pffuh,xtv4 3tq-x *5ywq 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.b/3r/kh, be wr0 kg and the elevator accelerates upward with an ac /rkb/3w ,rhbeceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. One force has a m8 stb h, o-ls+wy.cdc:agnitude of 8.0 N and is directed due north. The seh tyl8.cdb w-:sc s,o+cond force 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 the flatbed of a truckf)0z 6a tdmws9. 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 distanc0w9t admsfz)6 e if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. p76b9gf*f iyk4se ; e9zptc2k 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 time if the load iesffb;c2e6i9 kt pp4*9yzg 7ks not to slide forward into the cab?

  In the Atwood machinuhn*g h -d-h8le 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 friction and the mass of the pulleh-nd-8*luh gh y.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.606s: kqu 37amx,it: jdm kg and m = 0.40 kg, what is the tmdsu,: tj:i 6xa7m3 qkension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of bot( 9v8*y0bswd * cxcgyu/d9*qa1lccroks on a smooth horizontal floor with a force of 100 N in a directionr/ wayqd8lycs1 9 gc(xu 90cvc b*t*d* 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 hori wmww/3y wf ,t21gdelv.b6ng 6zontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box ant3. v2,g gfw6ewb yn6wwd1ml/d 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 ropes asavwle n8odxx7)8*3 x l shown in Fig. 4-2. What are the ten3xox 8*8 n)av7el dlxwsions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, uqh57 e4j h(cewhat is the mass of the traffic ligh(je e7hu5qh4c t?

  Two boxes of masses m and 2m are in contact with each other on a frictionlesir,s4 (.-f nmb1hf6ikj c 5ejfs surface. (See Fig. 4 (jskhni5f16 b-cjef,mfr i4 .-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2mw*9 3zzpfp:w6 sdxy v* are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force o:6 pxspfvw*z9 d*3wzyn the more massive box?

  Two boxes of masses m and 2m are connected by a ri62qe2 dq:u.2 ggurb to7zxn +ope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the ogt2q7eb.xizrqn :d6 2g+u2u connecting rope?

  Two boxes of masses m and 2m are connected by a rop 7vvsjsds 7,h3e. (See Fig. 4-4.) If the forward force on the more massive box is F, what is hj3v sd7s7 s,vthe acceleration of the less massive box?

Two boxes are connected by a rx6af5c9ayozvhwb4+g)x2 q6cord running over a pulley as shown in Fig. 4-5. Box 6)4fr +x haya6xw9gvb5zco2qI 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 between a 3.ex/7 uhob z6(j0nu1cl0-kg box and a desk are 0.40 and 0.30, respectively. What is1 (eblhx cju6 ou0z/n7 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 plastic on 6fg)m reya8+tj2i7gt7q nb7ev k bb6 :wood are 0.50 andfkm)8 +jrb2 yav7begqtnbit: g76e 67 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 + ai qmo)g7+6cigck8r0x direction. It slows and comes to a stop with a constant accelerati7)+m iioq 0a8ggrc kc6on 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 forv+ :tvl3xs+m a3v9kfv3u0yiece. A 3.0-N v3etv k0 vuf+mv39:a+lxys3i friction force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, tf0fnv5qas(k2y8wnu po * /c2at 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 of 10 m/s. Iw s.ab,gp0 e-st slides 50 m on the ice before it stops. What is the coefficient of kinetic fricti e-,a0 p.sbsgwon between the puck and the ice?

  During the investigation of aot27nh v d8ke.l5j9i i 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 prevailing conditions. E9donhelt58v i2 .jk7 istimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m a0 f 5wcumf0u4phbu4 c*re stacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes ishbfm54 uwuc4 0fu*cp 0 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. (9qmp ahg .f;(vSee Fig. 4-6.) The surface between the more massive box and the horizontal surface is spv.h g9q(f;ammooth 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 inclined plane. The plane is inclined ato b4 *pe0wk mafgb1p;fu9y u8t97 r+kh an angle0t pok9 u94uf1 pfbb7;gheram8*wyk + of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down lmj g x28*ur6gkoexbb)7rq-p6m7h 6 ba flat 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 smn7f9+6zqhnpna 9r lnsh gefx d.a9 1)aep .*4qooth 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 smooqivrc55mtp.j w6w h lx0352j wth 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 v 04tm gmzsvs:x* xn-yn37xz( an inclined plane, at a constant velocity of 6.0 m/s:vxzvm4(3 *t zn7 0mnxxy ssg-.
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 a s,(h8rvk (tu$37^{\circ}$ 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 do (+2b tyfg:jgs61ftviwn 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 50yma.4 :0zw90plw(lws:a xdrz 0 N along a rough surface. The cable attached to0yw pzl.arsza l 0xmw(9:d:w4 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 rest on a rou 2 wqq;dfix(4zpe 5t0jgh inclined plane tilted at an angle2 5zxdtwi;4jqq (fe p0 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 incline ish2 jszb+09 1jq7lqp jw 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 object and theb+l21wjq j9shj 0qp z7 plane?