Which of Newton's laws best explains whysi-7e9m4ypy hb,nx 7mxw,yl6f: acu9 motorists should buckle-up?

  When you sit on a chair, the resultant e;9k nnr(ok7yforce on you is

  In the absence of an external force, a moving objefelke r .7/8. /efxohkct will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned of /tnx7b;mo;wyf, while traveling in empty spacet/ b7y;xwn;om, the starship will

  A rocket moves through empty space in a straight ldvedygqpt:oqhh1-ig1d f25 /xdth7 ox- 9o +;ine with constant speed. It is1h:oqx -h-d5dq yifg gp 9e/tdo t;7vdo+21hx 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 is

  You are standing in a moving bus, facing forward, and you suddenly fall forwwnoe y/56ct- vard. w6 convt5e-/y You can imply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenly fall for e)n;ly*mzr2 rward as the bus comes to an immediate stop. W)*; zmly2enrrhat force caused you to fall forward?

  A constant net force acts on an object. Describe the motion ot/e hbbr1 :o) w o9qk:k4d7rpof the object.

  The acceleration of an object is invr 95z,+5qi zj dpbci5r0zo5fsersely proportional to

  A net force F accelerates a mass m with an acceleration nxi,/*g3ges-e bbbt fhu 439r a. If the same net force is applied to mass 2m, then thegngheu/3t*e b9 b- b34r,sfi x acceleration will be

  A net force F acts on a mass m and produces an acceleratbe+wp y8eo9 2oion a. What acceleration results if a net forcepe92wyob eo8 + 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will f9 -rz9iz61uqs 88ufo s nwpbn (nnz-)cly away. This is an illustrationn( n9i1zuso)runn-9pqzwb8-z6 cf 8s of

  Two cars collide head: z*/74kl ccdewir)ax -on. At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force tk7e /c*d4a zwlix:)rche 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 oj06x)vs 5sjjyn you wil x) j6vssj0jy5l

  Action-reaction forcesp2yu7eaype * 2

  Action-reaction forcn*7md/2npw ebes are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damagear ewat6k; r3zf/)j5 6bng; p7f xk8ye to the car. f ;gbk3r)8en6ryj a;waxz 6kp5te/7 fSince a lot of damage is done on the car

  An object of mass m sits on a flat table. Thx m,i9ns(sf.ae Earth pulls on this object with force mg, which we will call the action force. What issm.x, nisaf(9 the reaction force?

  A child's toy is suspendefpjda 707zq,tmcx 7 q5d from the ceiling by means of a string. The Earth pulls downward on the toy with its weight f a70 57fzjqqdc7,p xmtorce of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitzikauv6i c h.s.j9iv,9sxexv9 4o 9(xched to you with a 1500-N instantaneous force. The ball hits the bat with an instantaneous fs ho4.xxv9 s9z v9(uk jii ve9ix.a6,corce, whose magnitude is

State Newton's three lam 7r):c-u op1v qu:nfq1g.m2mydlfo7 ws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon /8l b)vo87cl4q q :ls yv;jrmgthan on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Earthm4lj87/ vrlq)g8;:bycv l soq ?

  An example of a force which acts at a dist /y-u+jx6ak rx*ky 6trance is

  Who has a greater weight to mass ratio, a person weigh2,ej tnbba 5ax 2f)m:ming 400 N or a person weighing 600a:fax) 2 me 52jb,nbtm N?

  A stone is thrown straight up. At the top of its path, the net force0uoh17k ;wm2yvcspabx:+u8h acting on i0 ha uwsb o: hupk18ym7+v2;cxt is

  A 20-N weight and a 5.0-N weight are dropwp+,2l:l9-zlu lypg y,z ey x4ped simultaneously from the same height. Ignore air resistance. Compare their accelerations.4el+2ylx-u p y ,p:zlzw9yl,g

  A brick and a feather fall to the earth at their respective terminal velociti , dk1o) w:b0hs-om5gp fi1udkes. Whi hudp sbo0i:k5,k)1m1g fodw- ch object experiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. *); d3vwmxrkpx2*26epvph tnThe elevatorp*t6v *)d2eh kpwrnp xxvm;2 3 is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an ew 7v3l)pvj thmr(w(t(zzjs*) levator. The elevator is t t *)psmr( )z3zjwv (7jh(wlvmoving upward, but slowing down. What is the tension in the string?

  The force that keeps you from slid x 3k c-:tf.4xmum yh6cwejfa20 wt xexu8-6)xing on an icy sidewalk is

  It's more difficult to start moving a heavy carton from; h*ewwe(q p)e rest than it is to keep pushing it with ew w)e (ph*eq;constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (fril;:1 ewyjk 2uyo-fx n7ct;yfn-o1 j k2:w exul7yion 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 to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thus we cacq8 xullvs0b9 -* 66zci- mttin deduce tu--6izcscx0vl b mli69* 8ttqhat

  A block of mass M slides down a frictionless plane in;yhv awj3m72f ij5d3aclined at an angle q with the horizontal. The normal reaction force exerted by the planevf3 2;h7iwam5ay j3jd on the block is

  A block of mass M slides down a frictionless plpc 7p rmz -twz70.om(wane inclined at an angle q with the horizontal. The nwt c7o.z0p( rw-zm 7mpormal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q wit,3 w ehiodawerygh747-c6m 7e h the ho,d e g6wm3 7r heaho-yiw7ce74rizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are rn2 ni::lo+b nh:r q6dveleased simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which hdobl:n2i:r6nq+v: nbest describes their acceleration after being released.

  An object sits on a frictionless surfa ;pcdo( re,em;-g lo.bue27dace. A 16-N force is applied to the object, and it accele;em 7 ; e-(d,lrudgeoo2cbp.arates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest u)u-5wh cuik)k uf/t3nd 3yc ;to 27 m/s in 7.0 s. What is the average foruyw-)u;kd)t k 3u3uc h/nc5fiward force on the car?

  Starting from rest, a 4.0-kg b 5x yfwc8oy/7yody reaches a speed of 8.0 m/s in 2.0 s. What is the net force wcf8ox5 /y7yyacting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 5j9-gt nv z63n o9p6;r*spo;va swkdw70.0 m/s after travelinwopn nvdaj 7 ;w9z-k3r;sptvog 9s6* 6g
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 10-kg mass flg;j3s*zfw2* f mru 4zrom rest;zs jmu2w*gfl* f4r 3z,

  What is the mass of a perso86qs v: jniely: ti3o6we20udn who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of b-6gu s6)lfiz the Earth where the accelubi6f6 -zlsg)eration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the obp2uo,zl 7zj - h0rxeud.c7 i.sject on the surface of the Moon where the acceleration due to gravityjrdl-upz x7iz.s02o7ce h,u . is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and objq v wan6/+nox(ect B weighs 40 N on the Moon. The Moon's (a/ 6nxvnwq+ogravity is one 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 rop6icjx q4s5q5oe. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward Sue scxij54q5 o6qat $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F 4:7 (+jlhn4iv(bms v x*p .fllbdajk 3acts on the stack, and it accelerava*xlb(vlmsn hb(4p. k l 4id:3f7j+ jtes 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 tqf/5 zo1tdib9h 9 loawq3y9(d he scale be reading when th9aow1qzy9td9(io/qb l 3dhf 5e elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides is-g po.glt4*g;lu qj ;n an elevator. If the mass of the person is 60.0 kg and the .g;l4-;jugg *toqps lelevator 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 nnjk6k/g g x ;5twk6 9b4peo7;tps hb3person is 60.0 kg and the elevator accelerates upward wi;t;gs tp6gpkj3 7ek6w/onb b5h 4xkn9th an acceleration 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 of 8.0 N :v l)8 m :btf)kxc(k hp+hwit1and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is the accelix:w)kk: 8vhtpf +hc(1 ltbm)eration of the mass?

  An object of mass 6000 kg rests on the flatbed of a tru 5c/x:80h etdn)x mko rniue17+s/ fpock. 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 distance if the load is not to slide forward into :+//x57okf rsim)teo0edxunn81p hc the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. +l)x myyis(:l,fe1h n It is held in place by metal brackets that can exert a maximum horizontal force of 9000y1:) ny lf+lx(ieh,s m 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, what isng5wnw3w; v(1 (q nfua the magnitude of the acceleration of the systgfwvu a1qwnn;(3 (n5wem? (Ignore friction 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, what ig*7 sd;iy.cfv(17n eh iarf m;s the tension in theff ;1(; ic.g*drnmsyv7i ea 7h string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a forc/gcpp ze4 z3n6e of 100 N in a pepcz z43n g/6direction 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 horizonuch+nm/s* d8a tal floor with a force of 100 N in */ha ucs+d8nm 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 box?

  A traffic light of weight 100 N is supported by two ropes as shown in z l4arx6i,v u)Fig. 4-2. What are the ten)ia6lz uv,4rxsions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is24c1 cfv/rakn btueq( ;p69 ww the mass of the traffic l6c(efpk429wu c; t 1qnbvraw/ight?

  Two boxes of masses m and 2m are in contact wi75u cbwc. cnz6f3p3bzth each other on a frictionless surface5bc pnfbw3uzz c673c .. (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact wimgv 0ogulr k+d/l0n-.th each other on a frictionless surface. (See Fig. 4-3.) What is the net force on thokl0rgg0 . u/mn v-dl+e more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If t wc +m5lrc s2r3/)ncqq k.pf mm2u)o0phe forward force on the more massive box is F, wha/curprkfp mmcq.50s3l) 2mc)qwo +2nt is the tension in the connecting rope?

  Two boxes of masses m and 2m aq a1.6z zp7j*iv*gkkq:ku,i vre connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acck:7p u* gk6qaikvz.1iq jv,* zeleration of the less massive box?

Two boxes are connected by a cord running over jc-b( bwi3ozcnwt4; f:4kx4n a pulley as shown in Fig. 4-5. Box i;wz4xno bnb wt-c (:4kj34fc 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 between a 3.0-kg box andvl jgk hayz(6b03a;i a, l(o)a a desk are 0.40 and 0.30, respectively. What is the net fo vjlb( 6h,3l kz0o)aaya(ig;arce on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kin)xg if00,. hc *b. cziwi8 qlorovlz.4etic frictions for plastic on wood are 0.50 and 0.40,l )b4 v.wo0, i80c*iczqzgiof.rh.xl
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 surfalouf 7rs+i iye-y(4sxph;,s *ce in the +x direction. It slows and comes to a stop with s;4p sr( +e usfihiy*7-xoly,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-i4b.6 l9p9pk7fb3py bw)jrso 9* rn xmN force. A 3.0-N friction force retards the motion. What is the acceler*)4k.xn6b ip b7swfp9rbpomyr 9 3j9lation of the object?

  A horizontal force of 5.0 N accelerpcl cu+.15adtzjf+n2f2e pg1 /b (t urates 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 puck is given an initial speed of 10 m/s. It sy(2/-z+vk dh nppc3oklides 50 m on the ice before it stops. What is the coefficient of kineo /2dnv(3p +h- zpkykctic friction between the puck and the ice?

  During the investigation of a tr jg pq5:sx8txca5t b051xjnx89du :eiaffic 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 conditie q1bj:8x xtcpn:uxd9g5s5i 58atj0 xons. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses mh;-e4lw*pn b 3i dgv-g and 3m are stacked. (See Fig. 4-6.) The surface between the more massive box and the hor ggiwepbd-n l*h-;4v3izontal 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 less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betweeba-c z1 aet*wyf ,qm8(n 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 coeffici(z c1wyfbaq*-am,et 8ent of static friction between the boxes?

  An object is on a fri.5ety+2f .qcfi tux9 actionless inclined plane. The plane is inclined at an angle of . a.x95qef+2c ityf ut$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat b vw;0kp7 d.zahill 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 j 1azpf0n-a ,cm4a/3gq3dztlsmooth 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 ang izc6i 9,v(b;sdte(hzle 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 vefxym s)e zm2i/7c/f9dlocity of 6.0 mi/7/cd z9x fsfmm)2ye/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-k6em e q,lp wd41lzf; 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 mashaz;dcy0 ;q h0s m 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 a x;jeo +ramn )fvzz8d1.btj0f7o mw1* long a rough surface. The cable attached to t j).vmx+;o18f dj n *eztbfa 7mr1zwo0he 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 at an 7n i.x8ps81yu t mv okyz3if6(angle(pvi7 o38kt1ixysfnum z.8 y 6 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 incliyd k:3 .r cya:jvu)nx9ned plane. The angle of incline is gradually increased until the object 9c):kdy j :u vr.xyan3begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?