Which of Newton's laws0c)dt/c u t/,a.9r-j gx sdsiw best explains why motorists should buckle-up?

  When you sit on a chair, the resultant 2s r-k ti01uum( :nspqforce on you is

  In the absence of an external force, a m: ddl8/zhmg, * cpr/tw)hy q2noving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned om hhq4vr 0j3teo.4m d3ff, whil.evhdh j0t3mo 44r3qme traveling in empty space, the starship will

  A rocket moves through empty space in a straikk7x na:bl-i 1m:;apught line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the ro kaixmp7::- u1n ;lkabcket in order to sustain its motion is

  You are standing in a moving bus, fac4sn/m2; 4xv laywizu/ ing forward, and you suddenly fall forward. You can imms/4xw; /alyzv 4u2n iply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenly falzwumzo ( gi,bd txf;j 35r02m7l forward as the bus comes to an immediate stop. What force cam0ozr;i jd5z7x f3ub(m tw ,g2used you to fall forward?

  A constant net force acts on an object. Describe the motion of the objectofh*omd q.5o9zi j. :t.

  The acceleration of an mqpehvp b5lf-m z9 imkpy5t92fm3)2+ object is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the same net f8i5 dbxn w87bv;1n 7cz mc6gcforce is applied to bcg67in wzcvbm ;xcnf8 d5781mass 2m, then the acceleration will be

  A net force F acts on a mass m and pmz4k(55g hzj9 lw o.zcroduces an acceleration a. What acceleration r.hk 4(m lz9z 5j5gocwzesults if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will ff29wi1 yhswlmt.w+8m ly away. This is aw. 1tiw w9lmmf8s+2yhn illustration of

  Two cars collide head-on. At every moment durin5x4d /c3 ylgw6qtim0 vu6d;*qlgr/plg the collision, the magnitude of the force the first car exerts y*qlm;wd g3r/xvupc d/i0l6tq6 l5g 4 on the second is exactly equal to the magnitude 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 object e7hkz:( 2s1ux zh88li0xapj cyxerts on you wilyhp:cki 10azxzul( 87sx 8h2 jl

  Action-reaction force 0b4q7e6lbp)ro+szw ,z qh)bnhat*e-s

  Action-reaction force:da. 23w me3df 0jnzr vd3o+rps are

  A 20-ton truck collides with a 1500-lb n*s/ b *wfdrrg,b-idg9:qpx - car and causes a lot of damage to the car. Since a lot off brg-w-r, x9*gd*p ids:b n/q damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this objfy2nhp/ccy: -.dpk(xgp 0c-u 4bb m+eect with force mg, which we will call the action fo.42- c0y ( :-bf/mcppgdeh b pcyu+kxnrce. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Earth oz6qk *9ux9cg m7/lt: chqw-rfmeb3d .51grjpulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction fho1 wrk5g/ j9mmzl 9r t-gc3q 6bu dx7:f*qce.orce"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. The bz-;y4 n6pauwqfq t ,a(all hits the bat with an pa;w(y 4qfqazu- 6tn,instantaneous force, whose magnitude is

State Newton's threec1kp)* psw fdmd,71dh laws.

  Mass and weight

  The acceleration due to gravity is lower on the Mop m.+ zoa*v*c*eay w,don than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon'pay,wz.vo* *em+d*c a s surface, compared to Earth?

  An example of a force which acts at a distad lh c7 go x*goxd++ct1(3lcz3nce is

  Who has a greater weight to mass ratio, a pers yzo*s0o0 4-l4dj*es s52q ix kjsrbh9on weighing 400 N or a person weighin qe 0i k5dr0z4y- x9b*oss24s*jhjlso g 600 N?

  A stone is thrown straigig edp;4f34gug 5r -gskkc a9ad 2p78wht up. At the top of its path, the net force acting on 7;-g p3a9g 8wfg dec2kkprd5s4iu4g ait is

  A 20-N weight and a 5.0-N weight are dropped simultaneously frox1vc md8l,lbh vr38q;+you z8 m the same height. Ignore air resistance. Cbv3lc1z dm ;y+ u8 l88vr,xhqoompare their accelerations.

  A brick and a feather fall to the earth ayv1x5zs.m(dbt t 3a z6t their respective terminal velocities. Which objmax6vb31.t(yd zz 5 stect experiences the greater force of air friction?

  An object of mass m is hanging by aj8k4r s11 hnra string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the ra41hk 8jsr1ntension in the string?

  An object of mass m is hanging byt.o +yztdo+ *w a string from the ceiling of an elevator. The elevator is moving upward, but slowing dootz+w+*t d.yo wn. What is the tension in the string?

  The force that keeps you from sliding on an icy gkuyu,ee.m,yg2 -el3sidewalk is

  It's more difficult to start moving a heavy cark*s2vs 94)j,bery /lu t0zwoyton from rest than it is to keep pushio4/ ly )ut9ev*k0 zrwsby 2js,ng it with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (fric 2+fxgp;xjmt9tion is present) at a constant rate. The ex29 ;fjxg ptm+xperiment 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 pb p xvr/8;,hj 1i+mb-t,xwktvelocity. Thus we can deducr 1ittbx-;wp/ j8,kpv ,+hbxme that

  A block of mass M slides down a frictionddekuw6.o3qn8e sgm8z.w4 r+, ou sh4less plane inclined at an angle q with the horizontal. The normal reaction husem .4wd kg+s,rz488.uw6d3nqooe force exerted by the plane on the block is

  A block of mass M slides down a frictionless ljz h57cigi. (kw w1f6plane inclined at an angle q with the horizontal. The normal reactiozwgwi1. 5ji6kcfh7(l n force exerted by the plane on the block is directed

  A block of mass M slides down a frictionles8 7g1kd)mx.hjz f w*smw8dq7ws plane inclined at an angle q with the horizontal. The gravitational force is dirq1m wmk7j78 hxf)w.sgd*dwz8 ected

  Two toy cars (16 kg and 2.0 kg) are released simultanm(vu ()tt(a)sud f (zj9rlv*vnj 4tgl+ quy5 :eously on an inclined plane that makes an angle of 30e with the horizo(l:yq(+u tstj vzavd()4lr9m t)(*g v5jnf uu ntal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N fo)m-kjqdxn8f v .t, +hgrce is applied to the object, and it accelerateq fhn8j.x k ),-vdgmt+s at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate frmi i8 3dmvp i:t(+y)r-lvu1m tom rest to 27 m/s in 7.0 s. What is the avm: miyt)r1 38pild+u(mtv-v ierage forward force on the car?

  Starting from rest, a 4ae5opcsz9 j4/(o ng5nv0ubn/ .0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force4n j0vo5cez( o/gpban 5s9/nu acting on the body?

  An antitank weapon fires a 3.qv3- j(sjnm8y*t lw3i00-kg rocket which acquires a speed of 50.0 m/s after travelintjn m*j y3q8 vwsi(3l-g
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 pusjut8n s . 8/yn0vky3yfh a 10-kg mass from rest,s8/yy k3n0. fyv ujn8t

  What is the mass of a c2v9 bsski a azp2y.f 1z;,3yjperson who weighs 110 lb?

  What is the mass of an object that weighs 250 N ojg c+ 6hcl-)wnn the surface of the Earth where the acceleration due to grag-ncj+cl) h6wvity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What irn 9jx5d.- 4albdh 3 l/qxosk+d k3jk/s the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of that on the E / +5dd na33 9b kkx/4rosdxjhl.kqlj-arth?

  Object A weighs 40 N on Eart4 kyc.;szuzv-h, and object B weighs 40 N on the Moon. The Moon's gravity is one sixtusv- z ;.z4kych of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war byskv0 b,d2uru..2 jazx pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if thedkv au,u.0s.2 zj 2rbx rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level fricti, vk+ 9ce5.g :.dwxg l5*qnxypvuc*zzonless surface. A force F acts on the stack, and it accelerates at,zlexgdxgp:v5k*5n .. q9+ywu *zcvc $3.0 \; m/s^2$. 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 wi8rz d 5tuhugz p5g)n+-ll the scale be rnzu+tp- d5gu r5h8 gz)eading when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an eleva/u6yq)a a ib1xtor. If the mass of the person is 60.0 kg and the elevator qba6i)x/1a y uaccelerates 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. *mrs+h8 cl4 qmIf the mass of the person is 60.0 kg and the elevator accelerates upward with an acceleration 4+*8lqm h mrscof $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-5+drmie8cs izeo+5*v mka: iyn9n(i 3kg mass. One force has a magnitude of 8.0 N and is directed due north. The second fokme e :(ir+visi z853c *5nd9+ainyomrce toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rest;x(y:xtx v*e us 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 st v(x:;*uxyxte opping 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 he4hd g:32nm0 ltkb4h7etpqj+ c1a0p wfld in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveliw 3e+ab h12ttl 0nd44: 0 fmqhc7ppjgkng 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 = 05oy8ok j gs9(2rc- 6 )jh+ekgmku ygq9.40 kg, what is the magych)- kku56yogjgke9+g m2 8j rsoq9(nitude of the acceleration 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 = 0.40 /8v m s* vxc 67p)4y4ehuoeyt+sfao*tkg, what is the tension in the string? (Ignore friction and the mass of the pul4 c*h)ett s 7mf*4a/6+xpve8 oysuoyv ley.)

  A student pulls a box of books on a smooth horizon) y81l -k4 b y8lcxbhwf ia*9sk5pt flbb9qo:3tal floor with a force of 100 Nl* -8tb5psixb 4kab93ybflqwk91 c8y)h:lfo 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: fdywox.ck97ow ;ro8 p0 unk3 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 .op3;: yd 87xk0nwofu9kwr cois 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 Fig. 4-2. m*v2eiv: - s zsw11cpqi/q p-r What are1qcv2 psz--pm evqwr1:i i*/s the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropesris4z-mh bv. 5 are 50 N, what is the mass of the traffic l4b5h.-m ir szvight?

  Two boxes of masses m and 2m are in contactvha9 nxar4u2/kk )we 5adx9:h with each other on a frictionless surface. (See Fig. 4-3.) What is the accelerehk9 524aaw h)kuxdxrn9:av/ation of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionles 7m-ielar*3- yzzyvw2 v-crv 6s surface. (See Fig. ycv -iwazlzmvr2-*yr7 -e 36v4-3.) What is the net force on the more massive box?

  Two boxes of masses m fdu6l; i6to1ov 8na;m and 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more ot; du;v al866nfi1momassive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (Sct owq .:gi**eee Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the:wcqi* t*e .og less massive box?

Two boxes are connected by a cord running over a pulley as shown in F 9bag2bb;c/wm ig. 4-5. Box I o;bmab 9wbg2c/ 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 7ep,w6 twsos ps 7rd/23.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force s6d2r pe,pso wts/w77 on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on ;w9ly p.ec( qhwood are 0.50 and 0qc.p ;wehy9l(.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 surface in the +x direction.p*dqxj() -4v(i j*puwxei3 hd It slows and comes to a stop with a constant acceleration oi*d-p*xu(v()xijqh de wp34 jf -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting ( u)cn e8 j6hp;qy(p rxy-9yidon a horizontal surface is pulled by a 5.0-N force. A 3.0-N fr9y rd8n;u i(qhpy)-ypej6cx(iction force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mas4f rcn p1p*y 2 yg58ac5wz,tn;-cafx ys, 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 nr+)lm l/vu5hikc)t+ of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck and the icmtr+)5h nu/l)lic +v ke?

  During the investigation of a traffic accident, policeq+9)nn:x i. hgbc d7jc 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 th +qdicj g9bc:7x.)nhne speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fi5, w. tf2wqvqwg. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the sw, qfwvt5q .2wurface 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 surf v dt,-;fb+r pgccba3-ace between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less massive box abvt-p;g, + c3fc rdb-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. The plane ,xu5we qis 1,tis inclined at an angle o5i,ute wx1, qsf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill.s p-lb ; zstx5gfg0l. 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 inclined p ntrarb+ n 4wex7r183qlane 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 plae/an:xg606l5is ss4ogrnr 6l ml-az 6ne 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 cr( ke 6aam z9q;s-el7velocity of 6.c; 9(6aq k -la7mrseez0 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 slide74p/xd u. vf+my irns8s 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 k2 1ikilsw5 s8down 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 along a rough surface. The cable attacnh. +6rh 35b xu jzqb06)seqr .gmlt1xhed to the log makes an an.13st .ub6rqb6r zmhjgx+)n0 5helq xgle 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 angle)yv7; gec yxu)d1psg - oyd;1)psvg-gu ) cy7xef $33.5^{\circ}$ 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 **hwh-bxix8 b we 15gp3f )rfhgradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient eiwhbx p*5gx-31 frf8bw hh )*of static friction between the object and the plane?