Which of Newton's laws best explains why motorists should buckl 4t(:trqqu5p ke-up?

  When you sit on a chair, n+e,fzia 1*ur*d6a hx the resultant force on you is

  In the absence of an external force, a ee, q 0atahk*i )+*twkmoving object will

  When the rocket engines on the sta*9)c f ni:g5sjyxice8 rship NO-PAIN-NO-GAIN are suddenly turned off, while traveling i c*)j9xi8c5gfy isn :en empty space, the starship will

  A rocket moves through empty space i8 fmbh.ac.la1:qm 6sp n a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must ba:pms8macf.h. 6bq 1 le applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you sud f-tphwrwi./, qmq4h46pk 3pqdenly fall forward. You canp/qp4im4fwr-t phq 6.wk,3qh imply from this that the bus's

  You are standing in a moving bus, facing l o*gljum ;(7vforward, and you suddenly fall forward as the bus comes o 7vmu*;jl g(lto an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of thnft9; euaj-ob 8ch.5he object.

  The acceleration of an object yzw :-fql7xsh8,ro5k is inversely proportional to

  A net force F accelerates a mas-us(1qzr(mxi 2a tw 2h/ mzhu*s m with an acceleration a. If the same net force is applied to mass 2m, then the acceleration will be(-hahi1m* /z(zxt22m rs wq uu

  A net force F acts on a aq- 28d.u8ccd k 7wewemass m and produces an acceleration a. What acceleration results if a net forceq.c a7kw ede288duc- w 2F acts on mass 4m?

  If you blow up a balloon, and then releay 3o ,8rs9mn 7,ghrc/uqiwd(j se it, the balloon will fly away. This is an ill3rriw,h/sjyocd(m,q 89u g 7nustration of

  Two cars collide head-on. At every moment during toqo1/*btgyxx n2wycp r,30-yhe collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force the second car exertro-1xy xc,0y2*y g 3b/o pnqwts on the first. This is an example of

  If you exert a force F on an object, the force which the object exerts 2 :rf :q 9;6pszgs:ahhf+w bagon you wilrgb; +h:sh:6zgf saap2 9:fwql

  Action-reaction forcesmas4dwd ud :qr,qnk:l+m- l)+

  Action-reaction forces a7i ,oftc 4s 1g96ptsfsre

  A 20-ton truck collides with a 1500-lb car and j /x .chfqzr *zs-sif.4tv0p;causes a lot of damage to the car. Since a lot of dar.phvf0x f4s-c/z .isq;* tzjmage is done on the car

  An object of mass m sits on a flat table..h;6qsgr*o w o*xs4 e+x6naz u The Earth pulls on this object with force mg, which we will call the action force. What is the reactionxageoh4 ns.;qzw6*u x+s6ro * force?

  A child's toy is suspended from the ceiling by fx1.gwj37ccjtt8 -jm means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "183cj tjftcw.mx-gj 7action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with w6srzmz /1p:r(mp.u pa 1500-N instantaneous force. The ball hits the bat with an instan.:r z6zpm1 pmsu(/ prwtaneous force, whose magnitude is

State Newton's three laws.;5hr0vap2 szp3k7q bu

  Mass and weight

  The acceleration due to gravity is lower on the Moon than k8uy myalmr (vagp.w29x*2 .d(r b3ag on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared p.kgal22rwyvdru x3a 89.( m y*am g(bto Earth?

  An example of a force which acts at a distance isiqn:3zvefg);2ilc 7e

  Who has a greater weight to mass ratio, a person weighing 400 N or a person weie4g,r8 xnksu277o 2 s:zxr gs*sf;chhgh ;gr 7:esru4 sh72 g ks2h8szc*xofx,ning 600 N?

  A stone is thrown stkjn ry76 e9h, x8v0 qij87fceeraight up. At the top of its path, the net force acting on 68ereixqj8k,j nvy 7eh70f9cit is

  A 20-N weight and a 5.0-N weight are dropped simultaneoz/cumcnvqprz7k4d 4 4n+b7z2yb t5v 8usly from the same height. y8kq7/n b2pbz5tcu7dznr4v 44 v c+mz Ignore air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal velocities.n/xxko g(fqcwis8z;a0j 32v- Which object experiences the greater force of air f8-zi2v3jx/gawxkso q (nf; c0 riction?

  An object of mass m is hanging byol/stt 2i( 9o kbfir/c e3m+u: a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tension in the s(t t2o3is+/bu /c:iklf9reomtring?

  An object of mass m is hanging by a string from the ceiling of an elevator.d(fugm6egu c /(x2n7g The elevator is moving upward, but slowing down. Wh2cn u7(gg6m/fd xeug( at is the tension in the string?

  The force that keeps you from sliding on an icy sidewao42os:tjvdc- s -e*milk is

  It's more difficult to start moving a heavy carton fromj0 :pf a0 32i garm7d91vrcunaar1r(hb0 hok0 rest than it is to keep pushing it with cons(da0o:p2 ba vrjr13fh kr 90n7hrca1 ug0 aim0tant velocity, because

  A horizontal force accelerates a box from rest across a horiz.t0+wlp c* -inima ym:ontal surface (friction is present) at a constant rate. The experiment is ri:i0y.+t lp nmca w-m*epeated, 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 a3.eew(ypdq+7kxn pk 7 t constant velocity. Thus we can deduce thayk k( den x3ppw7e+7.qt

  A block of mass M slidesw c3;;arn -vf(0w s pnx,.ffpv down a frictionless plane inclined at an angle q with the horizontal. The norman rfscn v,p.;wx 0 ffv;-a3pw(l reaction force exerted by the plane on the block is

  A block of mass M slides 7e :neh a*8e4tysgu9pdown a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by theae y4htp g*9n s8e:7ue plane on the block is directed

  A block of mass M slides down a frict/am9jo fk1m7n,j ;yft ionless plane inclined at an angle q with the horizonta,n9ot f1fymj k;/7amjl. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are releaseelfo0r.-b fa w4jp:n )d simultaneously on an inclined plane that makes an angle of 30jlfwr 04en)-:bpa f.oe 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 obex-6ot k5;9h /vwgik9 nks-dvject, and it accelerates a6xvik 5d g/skkw e9t-;n v9oh-t $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to tb;9*();e emz yebd en25dyr. iz cyr+.1eiuo27 m/s in 7.0 s. What is the average forw21m;rdy+eeey* t;b i(e ocnir.e5dzb)yz. 9uard force on the car?

  Starting from rest, a 4.0-kg bodyow)c10iyg b 1x,b 1 i5f;yfexi reaches a speed of 8.0 m/s in 2.0 s. What is the net foowy if0; b5e1fx 1ybi)xg,1icrce acting on the body?

  An antitank weapon fires a 3.+d*zde k9jzdgy d ;9a/00-kg rocket which acquires a speed of 50.0 m/s after trav;z+dz g ed/j*9ad kdy9eling
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 tn7:wa*0panqu i u+6 vche same force that you push a 10-kg mass from rest, aa+70wu6 cqvnnp ui:*

  What is the mass of a person who weighs 11 cpo z6tafr7 aop,4 jd6jaj1250 lb?

  What is the mass of an obj26we2017 celbxj-dd3w9g+xuaz4nu qtaui m +ect that weighs 250 N on the surface of the Earth where the acceleration due to aj+nu 6b x xu7det e +3a9wiwdc42q2lugm z01-gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth.1oh qh3 vcxf3vy.mh41 What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of that o ofc.3x31hhvq 4vyh 1mn the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon u e,qusiqx2,+. The Moon's gravity is one sixth of Earth's. Compare the,qx,2qu ieus+ masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on o 31*rkkjdkx4+7d y kyc3tvra 1pposite ends of a 5.0-kg rope. Sue pulls with a 1jvd3* 4xt1y+kc7kk3radkr y15-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 leverza2 ,pe8v r6,em .hxmcaxr 00l frictionless surface. A force F acts on the stack, and it accelx,e pr0z2 xarh ,m 0vm.acr8e6erates 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 el h42cl b1-dhbb j(/gxjevator. What will the scale be reading whenb-hlh xj(cb/g1bj2 4d 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 per ):+go leu8doizn n dgj+p )9lzrv+:3pson is 60.0 kg and the elevator accelerates downward with an z+ uz 9jopr8 gv)pen3dldg+:l)nio+: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 pers94gdtczw; mu;on is 60.0 kg and the elevator accelerates upward with an acceleration owmtc9d;g 4 ;zuf $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. One force ha e xc6(1e4nnbfs 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 ocfxnebn 41e6(f the mass?

  An object of mass 6000 kg rests on the flatbed of a truck.fws go9*+b9(y5 wd eer 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 stoppiewfwb e+*(99drsg5y o ng 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 ;) -yf0 uukaft+o i6w5aumng, 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 t60fk )muy;u n-iaw5fogt , +auhe minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shown xb5q gcv rb5 7)+3dqvtin Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the a ) gvbr3+xb7c5q5vqdt cceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m =w b-ca5( v22hifm kzk6 0.40 kg, what is the tension in the string? (Ignore frictb m wc-6zahfv5i2(k2kion and the mass of the pulley.)

  A student pulls a box q1hu0u0 c0jg gof books on a smooth horizontal floor with a force of 100 N in a directg1 jc00uhgu 0qion 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 b qx. 9/kcp ocoau+kc++ooks on a smooth horizontal floor with 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 . +o+9 okkc/pxccq+au the box?

  A traffic light of weight 100 N is suppor4 m6+yb bvre9f m:x/twted by two ropes as shown in Fig. 4-2. What are the tensions in the ropes+ y9bwve6 mr4b/mtx:f ?

  In Fig. 4-2, if the tensions in the ropes are 50 N,2326haprm/up0dmdwd(m -l q f what is the mass of the traffic light?u062pf /qr2dm l-d3a (mhdwmp

  Two boxes of masses m and 2mg) wrt7xyu3+szu:br2oot 2 -a are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more mabs2orwx ug y:2r t)3u7+tz-aossive box?

  Two boxes of masses m and 2m are .)is,hcm8)n(uv crw ggr-g i- in contact with each other on a frictionless surface. (See ih)r8)c .u-wis(-grg v c,g mnFig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (Seeb t6vcipfd:cn.3s. f , Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in tsn,3t6cpc: vdbff i..he connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If the )a(ntzz97xhv 2kf8l acys/-/ip*it zforward force on the more massive box is F, what isky l/7ncz a)ap- zvif89 z(tti/2 x*hs the acceleration of the less massive box?

Two boxes are connected by a cord running over a*fzss)u gej4.bp stej7. *g ci5m)l;c pulley as shown in Fig. 4-5. Box I o)ses mgs);gjz ci p 5.ujb*ef4*ct7l .f 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 bx+/zre olwpcxr8 559c ox and a desk are 0.40 and 0.30, respectively. Whac wlc/8op+ 5z xe5rx9rt is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of stat; r/fbbs ivo,6ic and kinetic frictions for plastic on wood are 0.50 and 0.6, ibvs;ob /rf40,
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 leveg n-b pjwrws(+f511yu )5oqe el surface in the +x direction. It slows and comes to a stop with a constant accelerati)1wqyp(+ fsn -1jeg5w ro5ebuon 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 5.0xc0 snzcv,kc 04 .zgh3-N force. A 3.0-N friction force retards the motion. What c nhv 4 3k0zc.cxzsg0,is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at a rate ogax9. 1 crc* cd,x.guwf $0.50 \; m/s^2$ 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 slvrm;oeed)v4q 5gu .t 2amt+yj6.x i 8fides 50 m f.tu)84 t re5o;+mgid yj.6mv2veaxq on 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, police find skid marks 90.obc;pj fyg3hf6+- e.s0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing conditions fh3o;fg6ejy-bsc.p+. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stanqw n8 n3,y9u p*r:daacked. (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 the more massive box, whaqn,ryp a*9u d w8an:n3t is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 5,vpedx*al m 54-6.) The surface between the more massive box and the horizontal surface is smooth and ta5*pxevd,l m5 he 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. o g8p;g2yzjqo wbg+ m+ah84,g The plane is inclined at an angle ofg;j b+ 8mg8zqgh4a2ogy ,+opw $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle of o; ycc 6cv zznvu:;q:n1 h+u qa2,em;m$10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclined plane cj e.)k0 ptxpm (y3,iv-mcc4l 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 smozj,lkr0vi.za 4ir y3c wn7 3i5oth 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 an inclined plane, at a constant velol *v3l: ;zy 6ll*ransmcity of 6.0 m/s. vl*;*m6lly:z3nasrl
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a mass(8f v -9zi1+d qbv /tahugl1rt 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 mass m slides down a rj5t fh 3c +vcu8sf*o6oough $37^{\circ}$ 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. The cable argbgf7vk-.7qdqutz (kqe66 7ttached to the log makes an anglbgu-(fqk 6 kez.gr 7v7q qdt76e 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 tilto, mnyxp82.xjpg z6x*ed at an angle oy.2gxnj6xx *8pz ,mpof $33.5^{\circ}$ 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 is gradua,fh,sfpg5m/n i amptbe-) *w 2lly increased until the object begins to slide. The angle 2 s,bhnp m ,w ptimf5/g-e)a*fat which this occurs is q. What is the coefficient of static friction between the object and the plane?