Which of Newton's laws best explainlen4z,v;fgjyd/ f ut.+*l)lcs why motorists should buckle-up?

  When you sit on a chair, the resultant force on/n,c3ndv l/ .:y r l.qfaw,qtt you is

  In the absence of an external force, a m w7 6lytug,qbc,eot 9/oving object will

  When the rocket enginek0i gdp- qiooq+c: lma66ps r2n7p-o6s on the starship NO-PAIN-NO-GAIN are suddenly turned off, whilem:inpp al6sqc o7+ 0 6q-dopgr-2koi6 traveling in empty space, the starship will

  A rocket moves through empty space in a straight line with constann)rgp)vm8/0qr-ajjoe si h 6:t speed. It is far from the gravitational effect of any star or planet. Undere p/6)o8rm jsrgh) i0jav:nq- 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 suddenl iez7 7h+q/8lceszf, sy fall forward. You can imply from this that i7s8/lef , eh +7czsqzthe bus's

  You are standing in a moving bu b6c)avb gz,v0 fel9j.ufr/;fs, facing forward, and you suddenly fall forward as the bus co;a0ec)vblfug/ fzvbr6.j 9,f mes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on : rs o+iv .k1tr5:my4ojh+u hgan object. Describe the motion of the object.

  The acceleration of an obj r:n-nr6zq0zvs 6p ncl:jk/j, ect is inversely proportional to

  A net force F accelerates a mass m with an ax2l4lxfekc- :a .chg5j+.td a5tmkbt u )3;lecceleration a. If the same net force is axde4lt5 a.c.fu)+:lek tka2bx hc- ; tl 3gmj5pplied to mass 2m, then the acceleration will be

  A net force F acts on akdd hy7vg)0 obt*u;1c mass m and produces an acceleration a. What acceleration results if a gt;*d ouhy7bkcd)01v net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon wih5 im;axxn0;eo lo a7;ll fly away. This is an illu;ohea;n5x 7; x iom0lastration of

  Two cars collide head-on. At 5kecsaxnbzi yu- n z*-la32;*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 the second car exert-n ;zn-a*b ua 5 yczsi*ke2xl3s on the first. This is an example of

  If you exert a force F on an object, the force which the object ex h+qdpbm u *xbyohk i*o2y:e54/ 64smcerts on you wi*od4km:u ie/mbyh xbqyc42 6+osp *5h ll

  Action-reaction forces; hh9,t, zfnli

  Action-reaction forcesxj+h7ysja )af ql168i are

  A 20-ton truck collid7 n,/v i y71of:-g1kv tsmlimies with a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done onis-/7nt y vm,17fgik vloi:m1 the car

  An object of mass m sits on a flat table. The Earth sgvaa1t o:zck(80r :apulls on this object with force mg, whic a:sk1:8to0gzac(ar vh we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Earth puldb3f-f8x ldn1bt *1he ls downward on the toy with its weight force of 81x1fb*e-dh n3b8ld tf .0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pil .wrw4w v*kyl/or :k8 vb1l0ntched to you with a 1500-N instantaneous force. The ball wnrylr8k/4*kvlw:0 o w1 l.bvhits the bat with an instantaneous force, whose magnitude is

State Newton's three labexbqv1eyh h) n 4+2:qws.

  Mass and weight

  The acceleration due to gravity nkqn0qu ;cc plg) 9t1;ow+fmx06ah2uis lower on the Moon than on Earth. Which of the following is true about the mass and weigq02c ;g9k0tlhan) m pw1u c;o6xun f+qht of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at al/,anq h1r+l u distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or ah6t ;,idji iq) person weighini6qidjh) i,;tg 600 N?

  A stone is thrown straight up. At the top of i(x7kdb 9 zrg:yts path, the net force acting on 9( ky 7xg:dbzrit is

  A 20-N weight and a 5.0-N weight are droppvl93w /o;e2 mg-)yyvs wyse9fed simultaneously from the same height. Ignore air resistance. Compare thve9-2 s9gv yem3wosw;ly)yf/ eir accelerations.

  A brick and a feather qicn sr47e ((kfall to the earth at their respective terminal velocities. Which object experie7q (k(4icnrsences the greater force of air friction?

  An object of mass m is0q4bgqtgr1yw 8,04f(d mi rgm hanging by a string from the ceiling of an elevator. The elevator is moving up at constant speeb, tyrgrmdq04q0i 1f 4(g w8mgd. What is the tension in the string?

  An object of mass m is hanging by a string from the ) )kz/wh t7dirozd/w:ceiling of an elevator. The elevator is moving upward, but slowing down. Whatr :w/i/do)d)tk 7h zzw is the tension in the string?

  The force that keeps you from sliding on an i f2g(pv9)5hna e, 9l4qb dtyttv.v kp2ob8 1qgcy sidewalk is

  It's more difficult to start moe:z bn2e ;*j4xsxoex(q 0faocw3* f nd --j3dkving a heavy carton from rest than it is to keep pushing it with constant velocity,f- 4(3ke cqd wzej3n o0o;*nd bseax-jf:x 2*x because

  A horizontal force accelerates a box fr0:/v0hvvvkn f9i 4oihom rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception thv/hifvi0k:vh94o v n0at the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down ;g )31 xl39twdrfghd nan inclined ramp at constant velocity. Thus we can deduce th wg9 3nxtd;lgh)fr31 dat

  A block of mass M slides down a frictionless plane inclined at an an 8jqs*68vpmm sz7yv-wgle q with the horizontal. The normal reaction force exerted by t zs67 pqswyvm*88vj -mhe plane on the block is

  A block of mass M slides down 8wana je7w2/la frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted bln/7a aw8we2j y the plane on the block is directed

  A block of mass M slides down a frictionless plane ihb7/ j0 aw5hainclined at an angle q with the horizonha07awb/5hi jtal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are rm-mq/x96.vj f npw9gdeleased simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make qpgvx d99j-. m6 /fnmwa statement which best describes their acceleration after being released.

  An object sits on a fn. a*1ew 0out4nshgwdrp4 ,-jrictionless surface. A 16-N force is applied to the object, and it accelerae4o .n, 1td-shw 4jga* 0rnwuptes at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 100 8xqy kvntkv:5(rl ls(4 s2eg+0 kg can accelerate from rest to 27 m/s in 7.0 s. What is the aveklt8 v52(n+e(lss rvx:4ky q grage forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2+a4 1isvf*p 3lf)de*rf5o ehg .0 s. What is th*pv*dfr+ g5 4esl1a)efi 3fhoe net force acting on the body?

  An antitank weapon fires p d. h.)tmqzsn8t 4g8lz9wy ;ma 3.00-kg rocket which acquires a speed of 50.0 m/s after .8y;)w8mdq4p nl zzts9mt. ghtraveling
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 samhghr;99kqu7 je force that you push a 10-kg mass from rehu 9;hk9rjgq7 st,

  What is the mass of a person who weighs yv +6g,uhqgtv3t0r0zl. hhs .110 lb?

  What is the mass of an object that weighs 250 N on the surface,r3,klpa72 yp aggiy/ of the Earth where the acceleration dr pi7,g/yla,kpayg32 ue to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Eart a gf:zjs6 mzy )*f(:q3f*egmhh. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is*f3 m ehsjq m:f g*(f)gz6yz:a only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the 1p5(gk;mnv oq Moon. The Moon's grav kvqp(1;mo5n gity 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 rh(f u;7:pvg cgope. Sue pulls with a 15-N force. pf7( ;vg: ucghWhat is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level phz -r33lkwp,frictionless surface. A force F acts on the stack, pwhz 3,lprk 3-and it accelerates 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 mh 9phwzwxo9viazj+l;ok93ew(g -,(scale in an elevator. What will the scale bip,z3l;ooxh j+ (9 9zwe9mkwh-aw(vge reading when 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 person is 60.0yt7o 3ly6xat /j n10ru kg y t1r76yt0al3nu jx/o and the elevator accelerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale ride3ex3v2 hyxh.ys in an elevator. If the mass of the person is 60.0 kg and t3h h3ex. vy2yxhe 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 force sw+mp t;kdk v3*3+ mozhas a magnitude of 8.0 N and is directed due north. The second moz * w;dv+pskk+33m tforce toward the east 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 isqzkwit, h64 )m held in place by metal brackets that can exert a maximum horizontal force of 9000 N. Whm4tq,iz ) kh6wen 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. rk)*z ljhfmeeh/ 6 ;5d ,u3xhh It is held in place by metal brackets that can exert a maximum horizokj56 h3xhe f/,; u*hhmr) lzdental force of 9000 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, whu0* owlr vsr/3at is the magnitude of the acceleration of the system? (Ignoreu/r* o0v3rls w friction and the mass of the pulley.)

  In the Atwood machine shown in Fi7f q:; o1cm ytpa*diy/g. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the o/ *y:f7m a;yqcdpti1tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a bo( s,f(8v gf7hetf:chmx of books on a smooth horizontal floor with a force of 100 N in a 8h(fe,gffv:ct hm7( s 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 with a force 1xx2ck v e2de. cgxq3;s)-dumof 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40.3d;qe1xcx. 2kxvsdm)-ug 2e c0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown in Fk: 1nv(xvrxg: ig. 4-2. What arkg :x1:vnr x(ve the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mv+a /1j(y:zkerl dp2 kass of the traffe(lap +r 1jd ykvz/k2:ic light?

  Two boxes of masses m and 2m are in contact with each other on a fricgzclc9 8h)d3wims,p 2 tionless surface. (See Fig. 4-3.) What is the acceleration of the more massive box?h gm8wl )z2s,p ic9dc3

  Two boxes of masses m and 2m are in contact with each other on a fricxtqi pic:7 g//:,vvij tionless sur/ /,p 7i:qgjxviicv t:face. (See Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If the fismn 5jhf.5up:5n nu 7orward force on the more massive box is F, what is the tension in the connecting ropej5u55n n:um.fhsn p i7?

  Two boxes of masses m and 2m are connected by a rope. (See +k0+v ,qt 8+7 6mvpn0wafpstryc .yboFig. 4-4.) If the forward force on the more massive box is myot 0vw,f v+0a +cpb8q7n tp y+rk6.sF, what is the acceleration of the less massive box?

Two boxes are connected by a cord runninq :x,7rtl g(dag over a pulley as shown in Fig. 4-5. Box I ofgxq(:rt, 7lad 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 kineti sawew xg 2+s8x9t-eu l.67qmlc frictions between a 3.0-kg box and a desk are 0.4 l .e9w7e q-62tw8sl+asmxxug0 and 0.30, respectively. What 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 wood ar a,7a y kne)+igj9dx c25a6tv/ fmrjt)e 0.50 and 0.42r n at9cdfxam +7/ gjai5kv6yj)),et0,
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 surg31zhs f:s9bzi3 6km uface in the +x direction. It slows and comes to a stop with a constans3zh3b uzig9 msf6:1k t 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 i;su.b aeq/x7a 5.0-N force. A 3.0-N friction force retards the motios axu7e.i;/qbn. What is the acceleration of the object?

  A horizontal force of 5.0 N acceleryl3uu-sm) ouqb- l.: oates 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 t6*te gtbes,8h. 0xzhbw9eo, is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. bt6s tb0w,zt,h 9eh8o.* xeeg What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a trafegjp3jqoe8f g7 ;u3h*fic accident, police find skid marks 90.0 m long. They determine g 8u j7;q*e 3jg3pfehothe 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.

  Two boxes of masses m and 3m are stacked. (See Figie+ds ee1a 9o,. 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, what is the static fric s dia91ee+,eotion force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. /kb, x u ,zj5ci78vepu4-6.) The surface between the more massive box and the horizontal surface is smoo5k,zui7bu8x,ev j /p cth and the 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 frictionu)ta nv aveyi.+bh 23-less inclined plane. The plane is inclined at an angle of t 2uae +ahn- 3iby.)vv$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle of 31og dm8jo v4ncsw7n ($10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth incliney xzjsd+-knyw ;:*9d jd 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 plan iksvcy4g ) (4dq1zu it12okz+e 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. vck9mf7l 4yvjpnb;1 directly down an inclined plane, at a constant velocity of 6.0 m/s.b1yvmpv 4 .cfjn7kl;9
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 o; lih6.to 7tma 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 dov:fugvei z 35 b izn/ubw(/)t-k/gre 7wn 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 sju,7p c5d ambi (+djch635c zgurface. The cable attached to the log m+h c a 3czj6c,jmd(ipbdu5 g75akes 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 inca sdbpa7,uq2qc n*03plined plane tilted at an angle of q,anb*pp3 cuq02d7s a$33.5^{\circ}$ 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 gradually inc w7myn*dqc*h*pfe v:e8upo*j: p/+k creased until the object begins to slide. The pco *pvee*u7n qc dh /y8:pjw*mf+*k:angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?