Which of Newton's laws best exp767zuub m 7ym-yg;ggplains why motorists should buckle-up?

  When you sit on a chair, the resultant inw;7-;s 2*x/d/ ubdiaenmn as4 qj o(force on you is

  In the absence of an externau z3kmo8um*/ bl force, a moving object will

  When the rocket engines on the starship Nwl1rj g2d 2:crO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the sdr1c2g: wr lj2tarship will

  A rocket moves through empty space in a straight line with ca8fzc;s* 9 nddonstant speed. It is far from the gravitational effect of anzafn;c d89d*s y 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 forwarfl8ko 5l qghxyxiyb9* /( gq6-d. You can imply from this tha 6 x(k*/yyl9oi q8qgb 5l-fghxt the bus's

  You are standing in a moving bus, facing forward, and you b8ndkcxl3i1:eqn alw( 7/u q)ldj5 -k l;dw-ysuddenly fall forward as the bus comes to an immediate stop. What force w;lk(x :lw)ca jkl3 u-beq l -/qdn8ny 1dd7i5caused you to fall forward?

  A constant net force acts on an ob*a u6h l y/mb04n 64lle;ruklmject. Describe the motion of the object.

  The acceleration of an object is ;9ohw bfn3(1y)r qwlknrv l0ptno,+/inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the same net forc1tdnl9gs0n lh1hz(d9nch; soa1+no1e is sa9 od1; ns0+1n nzhlng1t hc(9lh1odapplied to mass 2m, then the acceleration will be

  A net force F acts on a mass muius-m6,5)u 6nc)qv9 bhzm j m and produces an acceleration a. What acceleration resultsb)usnmjv m u-zh66)9 m5qu i,c if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will (8uu nxwjoty u17;k0p fly away. This is an illustratio oxnu8tyu 1kuj0; 7w(pn of

  Two cars collide head-on. At every moment during the coll7nucp k-zrl*z4i o4 z0ision, the magnitude of the force the first car exerts on the second is exactly equal to the magzi - 4u*pro0 7clnzzk4nitude of the force the second car exerts on the first. This is an example of

  If you exert a force F on an object, thvqpd(nw4y;7u p4sy( oe force which the object exerts on you willdnu7pq4 (( yso 4pyw;v

  Action-reaction force sr )k::xetfje (mz3z *1gihd8s

  Action-reaction forces arexn,- utk ujrrt.6 x*f+

  A 20-ton truck collides with a 1ihl,;, c: h; weh;cx4l7mmelk500-lb car and causes a lot of damage to the car. Since a lot of damage is done im c hh,;hmk4ex7 cl,:l;lew;on the car

  An object of mass m sits on pyi/x,e-ub vyeb oz0/ i.+-hqa flat table. The Earth pulls on this object with force mg, which we will call the action force. What is th.ebpqy e ib0uhi z/x-ov-y/,+e reaction force?

  A child's toy is suspended fr -hk8zd boih:u6q( g9yroy:) zom the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. q d:8yir(zbky o6)g hh:u-z9 oIf this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to youtm-rnjzo)u/ +6a75bp0 ( ed/odf jyhu with a 1500-N instantaneous force. The ball hits the bat with an injo ue 5/6 rbjmud(t/h-yd )npz o+a0f7stantaneous force, whose magnitude is

State Newton's three lpv fk2)jkd25o8z(w ly k9 yre;aws.

  Mass and weight

  The acceleration due to gravity is lower on 71f.7 pcqdqcd 7* ersjthe 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 p7qrcd fjde7.qc* s71 Earth?

  An example of a force which acts at axj*/w/ac7fd, gds. b v distance is

  Who has a greater weight to mass ra,tq(gy+p9 lm qtio, a person weighing 400 N or a person weighing 600 +yp l,tq q(m9gN?

  A stone is thrown straight up. At the top ofzd; ;y r4t26btw n5xi ly:eg4s its path, the net force acting on it ib 4t:2l5widsy gn;ry e4t;x6zs

  A 20-N weight and a 5.0-N weight are dropped simultane)xihyp 4vz3 )e xv -eur ;s5tf;*rx6rjously from the same height. Ignore air j z3it);)v-r xs*he 56;fp r4uxreyvxresistance. Compare their accelerations.

  A brick and a feather fall to the eg7l;ctd* )knnwvi 98,rht r2earth at their respective terminal velocities. Which object experiences the greater force of air frvh9;ekt2 dtri*,l gnnr) 78wciction?

  An object of mass m is hanging by a string from the ceiling of an el e.:wqgb2sq(kevator. The elevator is moving up at constant s(wbsqg: . qek2peed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceez)48u+ rvea6 phc7t jiling of an elevator. The elevator is moving upward, but slowing down. What is7je)t r+4 c vh8uape6z the tension in the string?

  The force that keeps you from slidingwj 1x2zp q5ko1.naok2he( 8r g on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is to keep h2j ,ef+o+ dslbou k5 g2ets(;pushing it with constant velocity, be fhbots2u,gk l;o++2je5d e( scause

  A horizontal force accelerates a box from rest acros0ob02gpmg h ,as a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the20,a h0ggpmo b horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclinerwpk/hv1 8l qypp 0n.ld:6/ghd ramp at constant velocity. Thus we can deyqp0 lhkwvgh8l 6/p1./rnd:p duce that

  A block of mass M slides down a frictionless plane incli0l 7m +u7ohyx;v3 vajlned at an angle q with the horizon7j;x3+ 0ahvouyl7mv ltal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down-n+kts9zefk:+r,hvz a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plan, n+srt:kez-zhf9v k+e on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angl4jeh 7ae3p+,dm3ckigr 9t nn+ e q with the horizontal. The gravitational forp9 +7,ngeh+4t i3acdjn 3mkerce is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclinee6)o/c j5r0 o6ch,iikersf5 l d plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration aftj6),icf/hc ike 0rrs oo 6l55eer being released.

  An object sits on a frictionless surface. A 16-N force is applied to g2nhku/i(:x tj ,-w2c5xlhapthe object, and it acc:ja/ui pcxln -(h2 twkxg,h25elerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from);gc 5nvo tq8m rest to 27 m/s in 7.0 s. What is the average forward force on theon)qg8 vt; c5m car?

  Starting from rest, a l3m,z1;b)kbxw b1ipp1v k3ar 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on the body?var1p ;x1b,b 3kk3i1 zmp wlb)

  An antitank weapon fires a 3.00-kg rocket wh 5dah(;,/4e ox6ht6cresoz :q m 2xsbcich acquires a speed of 50.0 m/s after trave,( ;d be5sa2tcr /h:z4che6xo6qomx sling
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 nhzm7heygf1ha,9: k bwpi -;+from res;a1,e p:gy- w hzh7kbfn9i+hmt,

  What is the mass of a person who weighs 110 lb?k +/q2 9bn kp 9*ufgd(.wtnfyv

  What is the mass of an object that weighs 250 N on the surface of the Earthlhleiar w rsv wpw822;*+k6 4q where sq4 w2va8*2; wwprlhk6+elr i the acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass a-dn)rm95r s r *g b;bc;cg9mfof 60 kg on the Earth. What is the mass of the object on the su9nrsg rabrc; f)d9bc;*5g- mmrface of the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N oxb58wf fy-*gqbv21g eew,f0 on Earth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. bbyf e*05q,wg-2e f v1fow8xgCompare the masses of the objects.

  Sue and Sean are having a tug-of-wa+ clythu x(0)qog(k/ s byx:h9r by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the ropehy)l x t:x(gbqksh9oy0( + cu/ accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A f b(zc t w+z47ir6p9ciqorce F acts on the stack, and it 4 6bz 9+ccii7tp qrz(waccelerates 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)) b04,vncpf g3vq h 11:xz0tublmrx d on a scale in an elevator. What will the scale be reading when the elevator is axl v : ,ud1xb0zhfq)b3mng)4vptrc1 0ccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in ac n ,xp.p,rd2 3;iyywqn elevator. If the mass of the person is 60.0 kg and the e 2p,q;x wdcr niy3,y.plevator accelerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale ridehmuj - ew5/3kos in an elevator. If the mass of the person is 60.0 kg and3hj /euw 5okm- the elevator accelerates 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 mass. One forcetc qujju4.v5; has a magnitude of 8.0 N and is directed due north. The second fo 4vj.utju5 ;qcrce toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 60rf-sic;(fm3 ei7v i p400 kg rests on the flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizonta f c;fr-me4si3ip7i v(l 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 f9ao. (rbzz y 5n17kpkhlatbed 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 the loadzk5 no1 h(bz9a.7ryp k 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 ks,rd wa 5ke:hw.olp3. a u6k3kg, what is the magnitude of the acceleration of the system? (Ignorau3 wa:s5 e,l .okp 36kdkw.hre 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, w 3+zwd7l1 jvlhhat is the tension in the string? (Ignord 31 jv7+wzlhle friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a foa , wh qw (lt,x.qqf278z4pcsdrce of 100 w zqx72q(cw,l dsaphf,tq. 84N 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 +,d58/la1g rkcwix 3o: q +jugq9m jrvwith a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and 1rwqiq,cg+mu lo39 /gj 8:dv rj+5xka the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is supportoaw w v357mj5led by two ropes as shown in Fig. 4-2. What are the tensions in the rowo7v553 lwamjpes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, zwhsv17h.vkmua/56 h m4 x-qlwhat is the mass of the traffic174-mwm .v/ xukq6hzhl vh5 as light?

  Two boxes of masses m and 2m are in contact with each other oy, .jqu 5v ur cgg.y*.a/nnr1rn a frictionless surface. (See Fig. 4-3.) What.n j.cu5g/g.n qyurrayr1v, * is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a f.n. xqxt. (zvnrictionless surface. (See Fig. 4-3.) What is the (zn.x. x.vntq net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig.t o5 m 7r2g4rmo-2glak 4-4.) If the forward fg-r2 mml5ao r7 kg4ot2orce on 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.) If teiwj*8krsd9d+ m- yu6he forward force on the more massive box is F, what is the acceleratimjs +kywe i8u 9rd*6d-on of the less massive box?

Two boxes are connected by a cor3 1zrnrys/*-zy:b v,b05 vfj 5wvzwgypn.e8fd running over a pulley as shown in Fig. 4-5. Box rp8zf / vz vwngfyy3ev.1j,50br5 :sw bz*-yn 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 statv (snjwg9a0f9 ic and kinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. v a9(nj 09gwsfWhat 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 on wo. r4 lx:mfox.*7 yc xic5fplv+od are 0.50 and 0.4y47.xof:m vl+xc. cx*5 rp fil0,
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 +x direction. It slows and comes to/b()q g bmmwq1v)cres8:mu ;n a stop with (;1e 8/g qwnsm)vucmmbr b :q)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 :i3 wnfq 0;cvcpulled by a 5.0-N force. A 3.0-N friction force retards the motion. Wfv:cwq3nci 0; hat is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at a rate oi ppo 85+s6oe6hi ,tj 8sb6dk(pgadn. f $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, a puck is given an initial spiy1h2tk55 troeed of 10 m/s. It slides 50 m on the ice before it si1 2o5k yhtr5ttops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a tr0n*nj z( c/2k aacb;fsaffic 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. Estimate the speed of the car when the brakes were applied.*n jafakc;2c (/n0szb

  Two boxes of masses m and 3m are sg*e* :och9u5k qb qdj:tacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface betweb5g: h* e jqo9u:qc*dken 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.xmm46* *g32y 4ink0v xouah lw (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, whawxugo*3*4i 6m alyh v2nx m0k4t is the coefficient of static friction between the boxes?

  An object is on a frictionle8ikaxrlgzof3q )y-7 9ss inclined plane. The plane is inclined at an angle oilz )q38okx9 -fr7yagf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hillqeph-cr7 rr0 0 )etny9q2u 4zdt4j 0ei 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 smooth inclihxd,g3 r+ zy )y+rld:fned 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 tcb8h.w5)ydgi57o*i gp9 y ebiilted 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 ant-: g+epkth-r 64c mfx inclined plane, at a constant velocity ofmrp g ftk:+ txch6-4e- 6.0 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 m slides downd) npc+oi z3w3 4k.zvb.nf)qb+v29 ugwb) mvg 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 ro3ojc0 :diit; fugh $37^{\circ}$ 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 roughj g cldak 3r.p ,13ech)rm1k0h /ierz0 surface. The cable attached to the r1g e lp/e.30cdhzm ,ha1i) r r3cjkk0log 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 roug9j6b 0.ccix-6+tns2z grldlc1(k 3 j t gvw.fch inclined plane tilted at an angle o23zwkrv i.c6 l +9(cn-cfj stxj. 6tbclg0dg1f $33.5^{\circ}$ 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 on6nl8*l8; zx31 onit2vdakzuj an inclined plane. The angle of incline is gradually increased z2n zl;nt6*kad388u v1ixoj luntil the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?