Which of Newton's laws best explains why motorists o*nngwnu8w/ z 6 82fadshould buckle-up?

  When you sit on a chair, the resultant forcjp*ia) lsn*cull(8m 3e on you is

  In the absence of an external force, a moving object wi t7gw1puk- 6u sq g )*byw1oic2grkh4.ll

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenlyvh-(x86 cupjb turned off, while x-jc8 u(6bhvptraveling in empty space, the starship will

  A rocket moves through empty space in a straight line with constant sp-k/ yyh4z yrq 8e3gyvr75r4fqeed. 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 ykz 435hrrgqr-8yy/ 7e fqy4vsustain its motion is

  You are standing in a moving bus, facing forward, and you hmi:.6 e9 gdqj 6otp3c8 w.afdsuddenly fall forward. You candmh eaf.:p6c69qj3og. w 8dti imply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenlok *ft+zjx 7 gpena89;dhan-- y fall forward as the bus comes to an immediate stop. What force caused you to fall forwaro*pfxj8 n+e9-tkd-hag7z ;n a d?

  A constant net force acts on an object. Describe the mmk r 8h2ez+9imotion of the object.

  The acceleration of an object is inversely prl m-k5 m3mpvo-oportional to

  A net force F accelerates a mass m with an acceleratioz(+ bfrtv;jb uw.5 ur2ha1in id0 .no+n a. If the same net force is applied to mass 2m, then the acceleration.ujat2 bwdv u+.r1in+b 5f (zno0rh;i will be

  A net force F acts on +1rr ydd7wn f)a mass m and produces an acceleration a. What acceleration result wy)rfd+r7d 1ns if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, a (9rpgklx4/8 (tsekt the balloon will fly away. This is an isrtp/eak(9 lg8x t 4k(llustration of

  Two cars collide head-on. At e0n6 -w3g-nv pikxvut +qh3n+b4x oy6 cvery moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the mav4vkx xw3nin h+o-6cn-uty30 bp+qg 6gnitude 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 objew5:lb0uhjtll+ybw q099*de+ gf* o jwct exerts on you will+y0fuwjtled 5l :* g0hbbwjw9ol9+q *

  Action-reaction forc2mh b8w:cj97psvz* zv es

  Action-reaction forces arys2nm7bmags 5(e6618fy yb q2. enors e

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage t6crs o4 jm52d)d fjmi/o the car. Since a lot of damage is done oo d26difj m5j) r/s4mcn the car

  An object of mass m sits on a flat table. The Eaqxfh 7wm :85z(aghz,wrth pulls on this object with force mg, wh57xzma 8( ,:qfzwhg which we will call the action force. What is the reaction force?

  A child's toy is suspended from theh n.u u51c3m5 bako8xo)af* cetcz14q ceiling by means 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 x*z mh4cfo1qe 5t358).on uacu b1kac is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous f(fnm3zigmo ,.orce. The ball hits the bat with aozn(3 mg,.mfin instantaneous force, whose magnitude is

State Newton's three laws l1(o9zus a a-)gx/zbo.

  Mass and weight

  The acceleration due to gravity is lower on the Moon th6gd 2hhsrpmb-gpzau:9(-n * l an on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Earthmgbh:-udh n2 spg( 6- pa*9lrz?

  An example of a force which acts at a distance i yt ggxc*.w(d 0za8mp8s

  Who has a greater weight to m7as k23pf6/-s lbxpc-a gaji8ass ratio, a person weighing 400 N or a person weighip3alcsxp-7isf/8- k 2g a6bja ng 600 N?

  A stone is thrown straight up. At the top of its path, the net forcer: wohwc4b);ybp-l4 e acting on it is obprybwl4-:w; 4eh)c

  A 20-N weight and a 5.0-N weight are dropped simultaneously from : qoft,5axui* tok3 k5the same height. Ignore air resistance. Compare their accelerationski5 at,* f :5xuokt3oq.

  A brick and a feather fm; e (63elksva6aoaa047ahaaall to the earth at their respective terminal velocities. Which object experi(a6hal3ae7ka4 eao v0ma6as; ences the greater force of air friction?

  An object of mass m is hanging by a string from the ceo0)) *oj)ogzo,k f5y+jkr 5 on/vrmikiling of an elevator. The elevatorri0 rvz) )o/ 5)oon,gkoj m5jfk+*yko is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string frogu*qwp ss bqs5w*k4 )o*5cx( vm the ceiling of an elevator. The elevator is moving upward, but sl*)xv( sck5bg*s4wuwo5q pq s*owing down. What is the tension in the string?

  The force that keeps yzi-. (cho 5vs.)miw ( 3kjkb;4ahyq seou from sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton fsd:x,hsvp+gb (gjr 7(rom rest than it is to keep pushing it with constant velocity, bervd h7sbj :, (x+pgg(scause

  A horizontal force accelerates a box from rest across a ht( o; g4gp.+9 yh,dtcs)yd 97xkcdwtoorizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain ;9pkxot ogdd)4g ,d9 (+.tchc yw ys7tthe same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down anc c0(7cw nj0o6ou6-cck bgnz 7 inclined ramp at constant velocity. Thus we can deduce that 7k7occgjnwcu-6 00 ob(cz c6n

  A block of mass M slides down a frichp8b/;cse oi p9ge() ftionless plane inclined at an angle q with the horizontal. The normal reaction force exerted bcp/fehis(; 8pbg)oe 9y the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angl6n xmt0(,2paftf pe/ v h1zz:ke q with the horizontal. The normal reacti2 ftth( kn, mf06ae 1xv:ppzz/on force exerted by the plane on the block is directed

  A block of mass M slides down a fri2d5f;nn qmia*ctionless plane inclined at an angle q with the horizontal. The gravitational force a5nm;d 2 i*nqfis directed

  Two toy cars (16 kg and 2.0 kg) are re sp.8h 88sxvxjleased simultaneously on an inclined plane that makes 8 s8.v p8sxhxjan angle 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 o::d/+n- ynr quk(97 vcgmljdt bject, and it admtnuj nv/dr-g79c: : ky (+lqccelerates 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/sk8 l8rdm: wm(l in 7.0 s. What iswlk r8m8ml(: d the average forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speb6 )tj(qq d7ujed of 8.0 m/s in 2.0 s. What is the net 7q j6dbut(j)qforce acting on the body?

  An antitank weapon fires a 3.00-kg rocket which ac.vmwnw(5aki 4 quires a speed of 50.0 m/s after tra (.w5amivn4kwveling
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 thrz-xhcie v9tkz*( 1mx 0c)lm0 at you push a 10-kg mass from rest*xhz cz-(e )l0mtrikcv9xm 01,

  What is the mass of o; 1gc80o ka 6ulpmpn pt+64cia person who weighs 110 lb?

  What is the mass of an object that weighs 250 N on theg(2ypt.k o( d+ 3tpvie surface of the Earth where the acceleration duett v(+(2. kg ppiodey3 to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on thee.z,hve, o0b 6picm *p Earth. What is the mass of the object on the surface of the Moon where the acceleration due *vi6e c,pe .bom h,0pzto gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moonb9l kanguxj )ex1w7- :hj/t (o. The Moon's gravity is one sixth of Earth's. Compare the masses of the objectsj(-n7) a/91x gwtu bxoj h:elk.

  Sue and Sean are having a tug-of-war by pulling on ;95 p)wrt c0txicb7pjopposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates xc5b c ip)j;0twr79pttoward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface..y z,ognl zj23 A force F acts on the stack, and it jg3y2oz.n l,z 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 stae0a4 u,k +p rcygit*(g5ppa;fdk)6f l nds on a scale in an elevator. What will the scale be reading when the elevator ifgey6 gtlfpi*4d+cr(0kk5 ) pp a; ,uas accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an xm9gd2m )nr1,b h8u8gza6qz xelevator. If the mass of the person is 60.0 kg and the elevator accelerates downwna8zx8gz9,hbg rm6qxu1m )2dard with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale ridelbl02xf.g s;v b5c l8qs in an elevator. If the mass of the person is 60.0 kg and the elevator accelerates upward with an accelerati52fllvlqxb8c g;0b .son 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 magnitude -b)k +xnc07h3yui hdra /dil -of 8.0 N and is directed due north. The second force toward the east has a maxd-7c -/l+a bh ih3ky0)urndignitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg jrp7cr y0n ldod8/.o0rests 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, what is the minimum stopping d/pnr. 0j0dc dl roo8y7istance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on thqqn 31jue)rz:e 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, what is the minimum stopping time if tnz )u31qrq e:jhe load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, ifk wiyho1f+)x0x a*u eb06i 6sr M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and th6hkbs ro 0 u)ex*6f0axywii1+e mass of the pulley.)

  In the Atwood machine shown ia*rry pcr)4w b ;p*r,fn Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tensiona wycrr4bp*f; ,rp*r) in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizonta6 z3q,ij 4ostcl floor with a force of 100 43oj6q cs ,zitN 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 wbn2 /0sbi3k ewith a force of 100 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 the normal force on the 2nb0ikse wb3/ box?

  A traffic light of weight 100 N is supported by two ropes as shown+1;,irxkqh zxx: tl *z in Fig. 4-2. Wzitzx kq1xxrh +l ,;:*hat are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass ij 5wjnv0;l2 ik /cdv4gp 7t:iof the traffic ligh/k c:p j527 ;jivgldntwi4 0vit?

  Two boxes of masses m and 2m are in contl ;vmc62by 4uhact with each other on a frictionless surface. (See Fig. 4-3.) What is the accelcyu4 bm6l; v2heration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a fricaysxoy8 ckq( b p8/n0;tionless surface. (See Fig. 4-3.) What is the net b0(k npx;ca y8q8yos /force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) lro/ * vzj6+ng If the forward force on the more massive box is F, jzgr+/ov*ln 6 what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) pgprr+1/ dc 1ijg3nam x8 )kv5 If the forward force on the more massive box is F, what is the acceli 5/p81k3rxrj)d+ cngp1gv maeration of the less massive box?

Two boxes are connected by a njp15+a)wqlzcord running over a pulley as shown in Fig. 4-5. Boxp5zljw 1aq+) n 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 kim9.pho6bmu,k+mc o )hnetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respecpbh o.cuo+,9kh )m6 mmtively. 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 plastic onv8vbfi/kf s ,rxj;u8+ jv8ez) zkav7nag+:1p wood are 0.50 and 7,kx a ajj1/kz)8fe8:+r 8zbug spivfvv;vn+ 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 88q 5rmek dnc6pvd*5tsurface in the +x direction. It slows and comes to a stop with a constant5 5*cmtnddv8 rpk6q8 e 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 pu yhtnh bg+t)4 (dbbu9/lled by a 5.0-N force. A 3.0-N friction force retards the motion. What isnt)duh+hy/9t(b 4gbb the acceleration of the object?

  A horizontal force of 5.0 N acikf987srzs/q p/i bfyq8 7o7zp47v jycelerates 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.p7)28dx ui90jhezvfge 6rsq puck is given an initial speed of 10 m/s. It slides 50 m d9s 80u iez qrf.7j) pevxh62gon 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, px8ww 9mf77t xgeibn;; /hwu3tb)r 3ixolice find skid marks 90.0 m long. They determine the coefficient of friction between the car's 7 gbe; nix3xti /7w)wu;9hwf8 mbtx 3rtires and the 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 ar7cfj6pt0we,09 q mtyee 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 q70c9et eyjmtp,fw6 0does 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 6ha t f+)tjfg3Fig. 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,a+3)gt fjft6 h what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. 7jr f8 .er 7rgy*hagqse8kp3..s;zk uThe plane is inclined at an angle of u;* q7rrr.e3j.kgepya k. fh8 s78gsz $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle ( glkqvtdi.(vh--wqzw )ns 51of $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smoogiw4mrw-o*x :xt(k6 vth 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 inclined plane tilted at an angl,-ul b ff+x7bd7tx gl*dxu5r;a/aq 6 ae 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* bneq-au .w4t ;*p7tbuot 2sg directly down an inclined plane, at a constant velocity of u;o7-u*swt.nag2*b eqp4t b t6.0 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 mzs tlf9q ja,1* 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 slides down a rough t:8 :sn26q)yr(x tw9m gb +xhsxd8my b:za9fp$37^{\circ}$ 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.w/s1txku d. 4ik4c mi a rough surface. The cable attached to the tkcii d/4. sw4.xm1uk 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 plane tilted attt8e k :x1bbz3px:qqf(96 ld2kw+ tvx an angle of dbwbekx :62p(89x qz3 f ltvt:qtk+1x$33.5^{\circ}$ 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 incli4 q-.+0jfrnx.cznaq ad8f j2kned plane. The angle of incline is 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 aa q.+4zf2kq.rnj-ndcf0ajx8 nd the plane?