Which of Newton's laws best explains why motorists shous8bu h,l j8 m*b-aa40x/f xqfz:y9ji xld buckle-up?

  When you sit on a chair, thebx2ha jdv0/ua44( xtsbls7 k( resultant force on you is

  In the absence of an external force, a moving ;ug) (d.ljnt)hv5 wwaobject will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are su71(0t yo(g5 wwq efhu2cggp.tddenly turned off, while traveling in empty spac we0otuptfhg(c2(g.1w5qyg7e, the starship will

  A rocket moves through empty space in a sap.y6 oi)rn;x traight line with constant speed. It is far from the gravitational effect of any star on6 )yi;rpax.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 movinzl1jm,t0 ez4 6wt .az32vevfkg bus, facing forward, and you suddenly fall forward. You can izlzae ,0kv2 wj3.16t4 fvmezt mply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenly yi c1i c67skpev8y/r:fall forward as the bus comes to an immediate stop. What force caused c 71i e6rsykic:p8v/yyou to fall forward?

  A constant net force acts on an obo26 l5g ygv4hbv7)ttf *pf s5mject. Describe the motion of the object.

  The acceleration of an object is inversely p x4xm( e+flx3rroportional to

  A net force F accelerates a mass m with an acceleration a. If the e25c1 imnjaed/: ..pvu -cxlvsame net force is applied to masse..2n: a- x/dj cv5 l1uepcmiv 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a.+qpxh)wsi+uptgrtf/;n1 x z i;z8 ;w2 What acceleration results if a netxiz)thq g 2t w++unzs;;;r8fpp 1ix/w force 2F acts on mass 4m?

  If you blow up a balloon, and then renx69wek5 t 3c7-2hth f7v kydolease it, the balloon will fly away. This is an i96hhy7 35ko2e vwkf c-7t tdxnllustration of

  Two cars collide head-on. At every moment during the collision, the magnitude5:gq zc ;pe4cv of the force th:p5ezc4qc g ;ve first car exerts 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 forceayyk 81ha5bu2b;m3 jm which the object exerts on you wilhmbk5ay8a1mb 3; jy2ul

  Action-reaction forces/dxz*g(/w qq u

  Action-reaction forcessu q3fj3 ;ywvdp:-mq 3 are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to the car/8 p0 r/fpm ,wqzrsn,fdpa91m. Since a lot of damage is done on the caw8s9, dqpa/ p10rpzf mf,/mr nr

  An object of mass m sits on a flat table. 9 8se(m62svua ;ukygxwr q1ua0lc6 4i The Earth pulls on this object with force mg, which we will call the action force. What is the reactione6u yi u8u;qas9 41g26cmxvalskrw 0( force?

  A child's toy is suspended from the cei *uxrf-tpt6y4 ling by means of a string. The Earth pulls downward on the toy with its weight force of xp6*tt 4fuy-r 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-rq zs31.ng(( os yolp+N instantaneous force. The ball hits the bat with an instantaneo3sg+pq(o.1o(lysz rnus force, whose magnitude is

State Newton's three laefim o1i 2 cmbb:9qk-7ws.

  Mass and weight

  The acceleration due to gravity is lower on-3 (e z3emqiob the Moon than on Earth. Which of the following is true about the mass and weig 3imezbe -3(qoht of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distance isbtfah 0n)d4y1

  Who has a greater weight to mass ratio, a person weighing 400 N or a person8gik4/)wayv/8h (sp:lp0v/z hv ny hu weighing 600 )/ia /h/v:npk y h wzvp48(gvsh80ly uN?

  A stone is thrown strvqwmibs5p m,w7v szpfkb:q0 :3e,9h0aight up. At the top of its path, the net force acting on hq 0mb7vm 05p:3pis,k sqbvew,fzw9 : it is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same7dy86ur wezk9b i*/ 4r3apoao height. Igna e kzdy*urp47o/ 6bori3a89wore air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respect kewqcjigk.698zsg98 ive terminal velocities. Which object experiencz9wc8i . ke69kg qs8jges the greater force of air friction?

  An object of mass m is hanging by a string from the ceilin 56msb) -lwel8)fbkxhg of an elevator. The elevator is moving up at constant speed. What is the tension in the strbk)l -mh6)s5xbwle 8f ing?

  An object of mass m is hanging by a string from the ceiling of an elevatoriow/.)pshe1*uyy l- x . The elevato* yp1)ew y u/.olshxi-r is moving upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icyd.9hn+8f( ewfpd0q/fu / mef s sidewalk is

  It's more difficult to start moving a heavy cartw63 9)5iik+tq pbyvg oon from rest than it is to keep pushing it with constant velo63g5 kvyo 9iit+w)pqb city, because

  A horizontal force accelerates a box from rest acroscc hp5+ou56gp s a horizontal surface (friction is present) p6p5 +ch5 cugoat a constant rate. The experiment 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 anxk f t,gsll)-9 inclined ramp at constant velocity. Thus we can deduce ts)- lx,ktl f9ghat

  A block of mass M slide fmv k a;r3yj hk9y 8(4ifvkm/w*q )z;lw;cig5s down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the blomaf ;g) wflyv4ri;j cvq3hmk8k5iw(y *z9 ;k/ck is

  A block of mass M slides down a frictionless plane inclined at an angle q w re(qt2 kif4:nith the horizontal. The normal reaction force exerted by the plane on the block is eq4ik( nfr:t 2directed

  A block of mass M slides doq23qmip43 ge3q pubu 94yf9vwwn a frictionless plane inclined at an angle q with the horizontal. The gravitational force is dirfiue3y qpvgbq9u 49pm33w24qected

  Two toy cars (16 kg and 2.0 kg) are released sim;. (i p1s pyqs80kkbkghhs,9multaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statemh0shpmqbksis.1g (y, 8 9pk;k ent which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is appliedqv7pwg,* bt2g4gye m0 to the object,4,0y2bt mggve pg 7wq* and it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from res ; k6t89tcb :grpa3)lm ,joya(jtfdq:t to 27 m/s in 7.0 s. What is t, mljbfgyjoa qptkt38 (r;9d6ta: ): che average forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What .k-4k+q k0zoh; 2)c ivl kmkxg;j/yccis the net force acting on the bomjki kh)c 4q;cyv20/kz .- g;ko ck+xldy?

  An antitank weapon fires a 3.00-kg rocket, *f ak+d;x:l*tkt06 9h jbfhwvf+glg which acquires a speed of 50.0 m/s aftegg l9,6j*ktlx + bwdfhakt0hv f*+f:;r 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 m) iuk ke axtn,d5*l.0gass from ree an*05kxdl). ug,kti st,

  What is the mass of a person who weighs 110 lb s 0 b.i2mhu+;ryf(abh15qvua?

  What is the mass of an object that weighs 2 noqwo:)9r i/k50 N on the surface of the Earth where the acw)q9rkn:io / oceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earpy4qxlvd:e p7nb-8 , 38xcporth. What is the mass of the object on the surface of the Moon where the acceleration due to g7,qoxd ycen-r l p8 xpv4p:83bravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and objecpb rj;,;j ky7zt B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Comjk p;b ,rj;z7ypare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on i2f+ c ee-f8njopposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope ace-+nijf8e2f ccelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frict ryrf9e6 .soo(ionless surface. A force F acts on the stack, and it 9o 6o .fyer(sraccelerates 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 r i54x;zduyz b3 rw+q3in an elevator. What will the scale be reading when the elevator is accelerating downward at 4 rdbr5+u w;z3zqxi3 y$4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is2bltpdr a4b 23l/f z/rct:.hd 60.0 kg and the elevator accelerates downward with an acceleration d 2rb at /f2lc34/p.l:bhrdtzof $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If the mass of the pikd,hc2loe l90m) mnq +/v+ jberson is 60.0 kg and the elevator accelerates upward wit+e2m/mjdl9o,0 b q+h)kcvnl ih an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces ayxlu0s zzb:d)xj 6)lg5oj: s1.cp ;vq ct on a 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.sz;p:j.1 quy sb)v:) coj lzd06xl5x g0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. Ija+ e/3luxai2t is held in place by metal brackets that can2a u xlj+ia/e3 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 held in qe-jy gdu jp(rwr: )1q8d,mn .place by metal br 1rd dn) .jw,juq:qgpr 8m-(eyackets 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 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,c; g+q0p 6 4oswkf83pgo(jedb what is the magnitude of the acceleration of the system? (Ign+s4 3gpkg ; c(dpoq e8wjf6o0bore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and -jr,m t ;uc1mwm = 0.40 kg, what is the tension in the string? (Ignore frict;mw1 urt cj-m,ion and the mass of the pulley.)

  A student pulls a box of books on a hkn3j01zmk (ua6 fz/f smooth horizontal floor with a force of 100 N in a direction of jmz/ 3f(k0fk6 u1znha$37^{\circ}$ 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 os0* ;cysfd3uq-vhx:n2l0e qg 1 / fascf 100 N in a direct: saq0l qgcsx1y02 u/fsvecdh n ;f*-3ion 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 the box?

  A traffic light of weight 100 N is suppordaxf4 w0v t+/s8gqok:;8tiyi ted by two ropes as shown in Fig. 4-2. What are the tensivq;4 y0ta8wi+t fi: gs8 d/kxoons in the ropes?

  In Fig. 4-2, if the tensions in the ropes ay31) .w(ou i 8hyhyxhny1qq+ore 50 N, what is the mass of the trafqh1yq 1o3nyw(y+)h.8xiu hoyfic light?

  Two boxes of masses m and 2m are in contact with each other on a frictio i snwvx.-mw)oim),vkp gq )qhn60 (2snless surface. (See Fig. 4-3.) What is the acceleration of the more massi w(n)s-)vogsmpi6 q hm,i)q0kx. 2vnwve box?

  Two boxes of masses m and 2-o 7tfk 9nqsq -k6mnb)c :jey;m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net f;9 bqesnnt-6:y 7mk)c-fqjokorce on the more massive box?

  Two boxes of masses m and 2m are4cl6 kpz.k)yqpn : dhd)b)x:r connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, whadkq kyz)p b4l):hxn .r)d:c6pt is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. ukwa2x6w+af()s a*f z (See Fig. 4-4.) If the forward force on the moreazaf+ )6wxf ks*u(a w2 massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown ink-q q* v8fae(u Fig. 4-5. Boxvq fauk-q(8* e 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 frictiov 8nj i-yq4;cbns between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on q4i ;8bc-nyvj the box when a 15 N horizontal force is applied to the box?

  The coefficients of 0tnziypabw 6sk1rkt zdd 1n /: ,/,6wyx;ece*static and kinetic frictions for plastic on wood are 0.50 and 0.4k6ped/x c tz,d*0wsnnyt;1ew :ykz r ,6ia1/b0,
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 dr+ aqt+7xur/ a level surface in the +x direction. It slows and comes to a stop with a crdt+7+xra /u qonstant 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 5.0-N force. A 3.0-uhw /w.; jcp 1(quj2zudfnj5u* 6,kapN friction force retards the motion. hkp q6pdw1fw5*z.u2uj,ujj;anc u /( What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from r3 as n20ev6uztest, 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 pr pfde,j0jm:zfscr89bhw/ q 6t /s+) nuck is given an initial speed of 10 m/s. It slides 50 m on the ice tje + szw)/d9h0r /spc , f:8nb6rqjfmbefore it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traff t piiy5g;s8s0ic accident, police find skid marks 90.0 m long. They dety5sig0sipt ; 8ermine 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.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betwz,vg*i-i 6rop een 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-irv*goi , 6pz, what is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. m u l2,q)pjk2k (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, what is the coefficient of stk,22kl)jm q upatic friction between the boxes?

  An object is on a frictionless inclined plane pijv3-k 1or iaznrwv-n.luq) 89eb-.. The plane is inclined at an angle o.1 aur pibv-e39no- jq- .r)z8vliwnkf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle of eel d.m e -5x6qcvc,u*$10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclined plane wi1g kn crh:yw6(th 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 tiltd1h3mwc gwq6)ed 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 4q mzs u.lw25bdirectly down an inclined plane, at a constant velocity of 6.0 m/s.m2uszb5lw4.q
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a mas:i1; stcq2+rlkbk 3 dms 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 sl53 nl9g8nwg:nz6k d r6jcndx :ides down 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 ndnafc:wxo/(qw79sxn3o8 :q rough surface. The cable attached to the log makes an angl wq8wqx:n9xn:7 s(o c fnd3o/ae 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 plan5ji5h ub,7x dte tilted at an angle oit,bh5du5xj 7 f $33.5^{\circ}$ 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 anta5lhhqgte : n0zvgf 21-p65sgle of incline is gradually increased until ttvn1htal ep 0h5z 6:2-5sgqfg he 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?