Which of Newton's laws best explains why motorists should 2oc- b6f0l ur4w nm j;1yeluf:buckle-up?

  When you sit on a chair, the resultant formh7:/8p1cq m ;rh cvqt/0m sxice on you is

  In the absence of an exx;+ :1fi6cykz i q/kciternal force, a moving object will

  When the rocket engines on thepi*z;fz i e9 6u1ztd l)-fur1a starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, theeruzdptlf)* azfiui1-;69 1z starship will

  A rocket moves throughjydlqk1 hea1 v z, u52n-fz3u( empty space in a straight line with constant speed. It is far from the gravitational effect of a u13v-5jlz qun(a h ed,12yfzkny 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 f5 a*ut:mrp3q vorward. You can impl: prm3q* au5tvy from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenly fa0 (mmyyzq6vqf :f 5n(all forward as the bus comes to an immediate stop. What (m6qf5v(my z :q fnay0force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the oy8h (nmx+24ccor ij8kch; z;hbject.

  The acceleration of an object is inve7tticn- o i1uz1s ,t4nrsely proportional to

  A net force F accelerates a mass m witgh6wc+x*; hqq h an acceleration a. If the same net force is appliedq+h;h gwq x*c6 to mass 2m, then the acceleration will be

  A net force F acts on a ma9 )c xcle;8y3d*-x)ufc fehb wss m and produces an acceleration a. What acceleration results x9 )ccy;b38cxwd el*h-u)eff if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will 9/wc1yw kz*+acxs wn,fly away. This is an illu*+wkz ,sa9nx cc/w 1wystration of

  Two cars collide head-on. At every moment during /a9:s- mjzhw1b vmo;y the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude 1j;amoms:zy/w-vb h 9of the force the second car exerts on the first. This is an example of

  If you exert a force F7jhh a-tm4iy2m/mk*t on an object, the force which the object exerts on you wi4j*y7k/mi m-ha t2t hmll

  Action-reaction force0xuv7c36t 9 s9eqrn rus

  Action-reaction forces ar)d mfu5 wz8)bxh3lh n.e

  A 20-ton truck collides with a 1500-lb car andik 4k-urtf9+b.t, *x rw ur-vv causes a lot of damage to the car. Since a lot oxfvrbuv.+ *t-k9rt ki-, 4uwrf damage is done on the car

  An object of mass m sits on a flat tabld9*o;lg vw :ise. The Earth pulls on this object with force mg, which we will call*9:id sl g;wov the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Earthm3e( nknrt8zvk* u a hly.w(24 pulls downward on the toy withktv*ly(krw4nz e8m.ha2 u(n3 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 s; nl+s/6 iczta 1500-N instantaneous force. The ball hits the bat with an ins/tz i +slc6s;ntantaneous force, whose magnitude is

State Newton's three la-d 2jh z.)hw- jml9gygws.

  Mass and weight

  The acceleration due to grav 4 bpa3*g0lm ;vqoqg,mity is lower 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 Earm*q q b;gl40ma3g,po vth?

  An example of a force which actsa 11s7mbb qcmi( 3lrpm,1sn1i elu 8e5 at a distance is

  Who has a greater weight to mass ratio, a persf6ph:t qlp c,8on weighing 400 N or a person weighing 600 N,pqftp6hl8c :?

  A stone is thrown straight up. At the top of its path, the net forccuk0*obqkz: + e acting on it :cq*z0u kk+ob is

  A 20-N weight and a 5.0-N weight arebwvbemd+z i4d +j k.8ntkm441 dropped simultaneously from the same height. Ignore air resistance dwj+ mevnmtkd4z484 k1bi b+.. Compare their accelerations.

  A brick and a feather fall to the eartko 0eosxi*;u2 (prv-2sa iox th8j)-gh at their respective terminal velocities. Which object experiences the grea2 ru i) k(pa eg8;0vho2tossj-*xxi o-ter force of air friction?

  An object of mass m 2yqm*3-cr+k bbid4qlp0 ct.ais hanging by a string from the ceiling of an elevator. The elevator is moypqc*2-4 lbc kd+aq bm3irt0. ving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ce)w*.sh/ hhjsy/ gt 2bmiling of an elevator. The elevator is moving upward, but slowing dogss 2h /)hbtmj .h*/ywwn. What is the tension in the string?

  The force that keeps you from sliding on an ic+e6ur)gw;2,sdmaz i k y sidewalk is

  It's more difficult to start moving a heavy carton from rest than it isa 9t ajkp-r7f1 to keep pushing it k fr 7jt1-ap9awith constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surfacecb-j,zy/d1 )56kn cztl6emk t (friction is present) at a constant rate. The experiment is repeated, jdn yzb/tmk) 5 6zce t-c,1k6land 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 conh, )f0l+d v 7(bdhhuln-qoa k*stant velocity. Thus we can deufn+hqbha 0 h(l7d),l dok -v*duce that

  A block of mass M slides down a fr7orag+d e 7 5l8ccp7yhictionless plane inclined at an angle q with the horizontal. The normal reaction force y7rp +hdce57ac log 78exerted by the plane on the block is

  A block of mass M slides down a frictionlnopv*3dgowxsxn7+/ w pz;u7d4a9 ( me l44tdzess plane inclined at an angle q with the horizontal. The normal reactionow +7ptl73nzp as du449 /x( gmw;*on vzed4dx force exerted by the plane on the block is directed

  A block of mass M slides down a frj 2eq.2bzl 0c,3r avpfteq2b0 ictionless plane inclined at an angle q with the horizontal. The gravitb,j2qae320r f2bzvc q0e lt.p ational force is directed

  Two toy cars (16 kg and 2.0 kg) are rele u*kjwy qs.(q2)tx g5uased simultaneously on an inclined plane that makes an u(2sy) tqx5kwg j *q.uangle 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 y wlh2/8spvy4,mg jhp z/-5moto the object, and it accelerates 8,ph4ys h//vmzl-po2m5 y jgwat $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in 7.0 qgnv8 ) nufzjlj. f9j*8i6kq1s. What is the average forwal8*v j)jj8f9 6nukqi.nqf zg1rd force on the car?

  Starting from rest, a vd4g*ry kz- vczf j2p+ ea4(/p4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force actyf +pjrz c * dezva4v/4g2p(k-ing on the body?

  An antitank weapon fires a 3.00-kg rocket which acquiresr sv3h6 g35dbu a speed of 50.0 m/s afterv3 5 hgud3rs6b 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 10-kg t uqbl*z,6rx/ mass from reu,xl qr6/ *tbzst,

  What is the mass of a person who v(,wn ddk*-duweighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Earth wher nzdw(rs)vc;* qb .+dee the acceleration.d )s *qrz(dbc +;wenv due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on thbn s 2m1kf-h-tv,: wlge Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is onlyv,n b1l :k-2 t-fmshgw 1/6 of that on the Earth?

  Object A weighs 40 N on s5b:9mwveoveju a1w8koi8xgza *( 5 1Earth, and object B weighs 40 N on the Moon. The Moon's grjz8a8(b 1ov9:o 55keewix1vw u * amsgavity is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by f9,c -8hzllp+9 ta7*pxxlmwdpulling on opposite ends of a 5.0-kg rope. Sue pullsdpl ,-xmzfl tw apxcl9*+87h9 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 frictionless sur)-oh08x:nibeho/jh u: b tqo+ zvgj(5face. A force F acts on the stack, and it accelerates at :t8(:v/ ijz+5 )hgo ux-jhho obq ben0$3.0 \; m/s^2$. 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 elevwcgyp8odrnx (s g02o.:j ee.3ator. What will the scale bgo(r : ds e. 8ecng0.2wj3oxpye reading when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If 92e5 warvwy(g0 xby)t the mass of the person is 60.0 kg and the elevat()wyxg 2vtwa 590 ryebor 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 8jzozq ;v. m8athe mass of the person is 60.0 kg and the elevator accelera. z jo;q88vzamtes upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mabh0x9nl,c *d*aa ten, ss. One force has a magnitude of 8.0 N and is directed due north. The second force toward the eat,c 0n*xba a h*,l9endst 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 truck. It is -cuy22ap-vokhhc0; cvn h ,a4 held in place by metal b hao h;4cnph-,ac0v - ykvu22crackets 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 the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is hel z*e/g k*4xjkld 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 stopzje */k k*x4glping time if the load is not to slide forward into the cab?

  In the Atwood machine shown sq1h 4a +kt . t0(dpn(zyx3g24hnlsvmin Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the accelerastx+nmlv4 3yh((n4s0 ap.gt khqd2z1tion of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine 4 f+zrn rt 2**na0eqfm,j 0rxmql+wp1 shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pulle0 qnx *m+4r2t *zq,wp0r+1ln j emfrafy.)

  A student pulls a box of books on a smooth horizontal floor with a force qrgbe 0qr6 b2.of 100 N in ab6 02qerg.br q 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 wis.de: vd)nzb;smv -8 ith 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 on8db:ns) vmd. ;evi-sz the box?

  A traffic light of weight 100 N is supported by two rope - n myhto/gw9cah5/yz0 ;vsu9s as shown in Fig. 4-2. What are the tycnm5a-;y gtuv0 w/s9o/hz9hensions in the ropes?

  In Fig. 4-2, if the tensions in the ra5325 ptl hkrk(wcq/c opes are 50 N, what is the mass of the traffic l 5cq/2 ar5lk pkt(wh3cight?

  Two boxes of masses m and 2m are in contact with each other vkvb)4)nm 8y q dugn(9on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more massive box?ynm4 g(u n9bvkq)v8d)

  Two boxes of masses m and 2m are in contact d7ca )custl +1with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on tlcu 71ad +)csthe more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-;)-uz0sdil f/x e u0tu4.) If the forward force oz u/;sfx-uud0e0ilt) n the more 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 Fig. 4-4.) 2whz 7zkc4t(fIf the forward force on the more massive box is F, what is zt7z cw4f(kh2the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as 6 ij4zw; hj,rcxeth33shown in Fig. 4-5. Bjezjt h,hic 34r;x3w6 ox 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. yof93icvs, q*0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box whe*i oys,3f9 qcvn a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are , 1(d7io2;o vyeg s u)7lofjss0.50 anf 1l)uvosojd7s(g oy ie,7s2; d 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 surfac :v9wdkh9:tmf5xn a x;w 4 mu2kshz0:be in the +x direction. It slows and comes to a stop with a constant ab x : 9zskwh wx0:9d;um 5m4fvh2tnk: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 5.07u ux0tr su ;,q-/w-fpersr 1b8z cj9o-N force. A 3.0-N friction force retards the motio9b-f jqzu7 wxs1sr ;uu8p0o t-c e,r/rn. What is the acceleration of the object?

  A horizontal force of 5.0 N acceledvwtyj-h6y,; 6 oiyw/s2r zw .rates 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 spee wx:qxzz1 0 erml6d*8 p0w8dldd of 10 m/s. It slides 50 m on the 8qwd8d x06z*me:lrl10 pxw dz 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 find skid marks 90.0 5s p2p,9 wce, jb/xwqxm long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing conditions. Estimate the speed of the c5/qjp2w ,e psw b9,cxxar when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (Se 9wrq;2p- v* wg4rykq8 pxm8d l0fhuo8e 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 t ru0vq xmgw4r2 olw;p -8p8qf* 9y8dhkhe more massive box, what is the static friction force on the less massive box?

  Two boxes of masses m and 3m are sb52 l -yyf-9ve.7hic-zh*: hxvvnlxntacked. (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 thv yn9hz2- 7* .iyvh-nlbhlc:fx ve-5xe more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane,s*mg,ii6 jhbbegy a/tkb4.ys -;d2 d is inclined at an angla/6d-dysy4;sbeb ,jmg *t hik,i.b g2 e of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angljj)t6q c)*gzcpij9v 9e 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 inclindr.+ ria4n*zr;mvqlm61akne :9j z2ied 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 angle of ai.l +w8is (paa,. kp8kr m2evmpj (o*$35^{\circ}$ 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 fy /j1r;v(nr78w xf0mf+fbj8n2ct p fa constant velocity of 6.0 m/(rmjf1; nybt c8f7xwv0f8f/n +f pjr2s.
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 igz ovv8 w 06kodrv/gz (t6n01a 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 dow-yn 8sp-ppn;srk wj 2,n 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 a; (mjany8fhfyn iu 29;ye7d7weighing 500 N along a rough surface. The cable attached7y8y y; hum7e2(d9fnai ;jfna to 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 relefj 2:5l0fcvbk ased from rest on a rough inclined plane tilted at an angle o cvl: b2f5fk0jf $33.5^{\circ}$ 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 inclinp,(d xtyw b65re is gradually increased until the object begins to bx tw(6yr5 ,dpslide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?