Which of Newton's lawsx2um nxn-dm5tmi wpgs9wto(*3: . y2f best explains why motorists should buckle-up?

  When you sit on a chair, the resultant force on you i.zeouc9:i sh*s(j qh.u 3d/ jxs

  In the absence of an ext mwgtnv )k3:*pernal force, a moving object will

  When the rocket enginy3rtn4 w x84ovwl.3t ges on the starship NO-PAIN-NO-GAIN are suddenly turned off, while trav8n34tr xwg3 vlo.w t4yeling in empty space, the starship will

  A rocket moves through empty spazr6 0:/fw a3cqnswuk5ce in 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 be applied to the rocket in order to s:3zun 6sa k0wq5/wcr fustain its motion is

  You are standing in a moving bus, facing forward, and you suddenly fall forwymqv;rb32l3/m e3o mk2 yqb d9(9xni tard. You can impl;/ 29beyoqm m vd3 9( mltixr3k23bqyny from this that the bus's

  You are standing in a moving bus, facing k 7iaagbm 8o.0kj+v9 aforward, and you suddenly fall forward aom.v98b07k a+ ijaakgs the bus comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of 1 f ;nocn4/gse+:ki uothe object.

  The acceleration of an obj +n tzy v7zroj3r0 eamd5mm74ub.fw)(ect is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. Ifs ,o7i/:7sh r j8bogzd the same net force is applied to mass 2m, then the ab so:hzgi / ,ro77jds8cceleration will be

  A net force F acts on a mass m and phss9l p;l5 :o aeen1n-tp3;pfroduces an acceleration a. What acceleration results if a net force 2F acts on m3pnt5s;on p sa9ele fh;l1:-pass 4m?

  If you blow up a balloon, and then release it, the ballook*pcror(z*p7y( 3wzl n will fly away. This ilz k*w(3pzrp r* 7oyc(s an illustration of

  Two cars collide head-on. At every moment during the collision, the magno/7lr ow9u)l zmc 34dvitude of the force the first car exerts on the vc7o /l) rdmo34l 9uwzsecond 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 34urz0x*en.63bftihesn0bwexerts on you wibzrisewhe tb0306 u4*fnx.n3 ll

  Action-reaction forcm qa c vfx5/87w,6nazwes

  Action-reaction forcdtp 6w:44 ibkles are

  A 20-ton truck collidestr/re+jan; pey k 5f.f)dgl, 3 with a 1500-lb car and causes a lot of damage to the car. Since a lot of da;dftr.j)y+ n, 3fke/5lparge mage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this object withew a5j u:gti(:gb1- epa 0eo+j* ydw,y force mg, which we will call the action foioj *wyd bea:uyggpa,5wt+-e1 j0:( erce. What is the reaction force?

  A child's toy is suspended from the ceiling bn9o9) lyok2l ny means of a string. The Earth pulls downwardlln 9n2yko) o9 on the toy with its weight force of 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-N instantat -ir*imj3i -k wys4k6neous force. The ball hits the bat with an instantaneous force, whkr34 k-s- iii w6jym*tose magnitude is

State Newton's three l)w4c)wfccrm7 zj) u7uw/y.lmaws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than onbm svy*elj67nc ya,3 ( Earth. Which of the following is true aboubs y3m*( j7,ve l6ycant the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a d-gpu wde22 s.histance is

  Who has a greater weight to mass ratio, a person weighing 400 N c j tf/j/rjo77-2yyh dor a person weighing 600 N?hfyy- 7/2jdt7 cojr/ j

  A stone is thrown straight up. At the top of its path, the net force actingj21w3kb qs7c b9eapas1./)wca*h fjl on itq2phbk)l fa e7s ba1/*cw1s . cjw93ja is

  A 20-N weight and a 5.0-N weight are jujfask/;;ca +n/,;drg9 x jedropped simultaneously from the same height. Ignore air resistance. Compare er kdju;f/9sag /n;c,jj+ ax;their accelerations.

  A brick and a feather fall le+lsd .j0iz +to the earth at their respective terminal velocities. Which object experizlsjd e+.l0+ iences the greater force of air friction?

  An object of mass m is uftg/v9od merf)x4owc9rw2, sks22 3hanging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tw)owror e22/29sds,v 9kfm fc g u3x4tension in the string?

  An object of mass m is ha9+20uotz9 w).kcl ac r.dlrz/6cnvmq y4 rq2pnging by a string from the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the tension in c29nw4a 0.c/tlm.)kzy 6 cpqqo2zurdr+9 v lrthe string?

  The force that keeps you from sliding on an iny w.z c1*oecf9/sq9 ocy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is to k(5grhh -, mvr00 mi2*tjte lygeep pushing it with constant velociemggtlm0,0h25 htvy* rir j( -ty, because

  A horizontal force accelerates a box from rest acrosmz1 jlnty jn9+9z6k7n+f s0ovs a horizontal surface (friction is present) at a constant rate. The experiment 6n9j 9+z0not+ljnvmfks7 z1yis 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 velocisp2n2xwi2z:hma+ho *.o2nt+r:b auo ty. Thus we can deducit2zo: a2n*a u 22mpr. hwhsx+n:oo b+e that

  A block of mass M slides down a frictionless plane inclined atag7+ dz ;yss(g an angle q with the horizontal. The normal reaction force exerted by the ps asg;z( dg7y+lane on the block is

  A block of mass M slides down a frictionless plane ie( )nsb2 c0c.3u fjbj:wdfbh,nclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is b3. 2jn:fu(cc,ebf )s0 hwdbj directed

  A block of mass M slides down a frictionless plane inclined at an angle q withj8zf 10o* q akzsq q95dyajq6. the horizontal. The gravitational force is directj5*q of0kzjys1qq qad6.z 89aed

  Two toy cars (16 kg and 2.0 kg) ar/pp u+3j )wcvtr.dh/k,xg szr 5/7dbse released simultaneously on an inclined plane that makes an angle/j/+kcpd,rs ruw/.v pbzd x73ght)s5 of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictv4ej te:u16 nwy *ppg6ionless surface. A 16-N force is applied to the object, apn:e6*ute 6vjp w1 gy4nd 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 rest to 27 m/s in 7.0 sce3fk2mqrni;m j5pa;wr7 ,f6 . What is the average forward force op5fa kw3er6q7j ;,m2nm irf; cn the car?

  Starting from rest, a 4.0-kg body reaches a spe5;ls. b+yhn lych5f x,ed of 8.0 m/s in 2.0 s. What is the y l fb5hln x.s+y5hc,;net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acqzj.-u 8mac+pguires a speed of 50.0 m/s after travcaju8mp+z.- geling
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 yagp.+ul4 y f291,rv2y xn azamass from res2+vgz2a.r x f9pa ny41yuy,la t,

  What is the mass of a person who yp,xqcxp)66j ac9a 0h weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the zg( eoqni hl+ 0577jwuEarth where the acceleration dnog5elu(zj77ihw0 +q ue to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. cs i9vb2;o,z wiu1h0bWhat is the mass of the object on th 2zo9;b bh,vc usiw10ie surface of the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 402)bp ,neu :mer N on the Moon. The Moon's grav:p )mu,en bre2ity 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 zeo9:wh)t;j s5.0-kg rope. Sue pulls with a 15-N f9; hoewz )tsj:orce. What is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface.,fign m be4t 1s y2x7:p:xine9 A force F acts on the stack, an7:xi 2fs9tpen4egn i b1,x my:d 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 4807(j+ z) srdxuu)jies+ N stands on a scale in an elevator. What will the scale be reading when the elevator is accelerating (zu rsisuejjd+x)+) 7downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevf gwt9hr-zv.i 2v1m c-ator. If the mass of the person is 60.0 kg and tc1tigh-zm 9vwr2vf -.he elevator accelerates 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. If the mass of the person is 605z0f.p82pj9 mk )zfpc1pv7z( bxrr ys.0 kg and the elevator accelerates upward with an accelerj2z0 p(vzspk71x.m 9py)8ffcrpr bz 5ation of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. O 6ro qci tap07bny)4hmas4q .+ne force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.q )moy4h0p+scba4. n i7at6q r0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is hvc+ a6ciy2 ; wchtn),beld 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 distance if the load is not to sli2acv; ctwycb)i6h ,+n de forward into the cab?

  An object of mass 6000 kg rests on thzyt z(rr k.(,2jtf l0oe 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 oz,ykt(.fr2 (0trl j zm/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 m1jhb5ak)t-g4 i a7 doe = 0.40 kg, what is the magnitude of the accelerathe5g7dti-oajb) 1 ka4ion of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if x stcg e 1tq.cw4n hrk*;vc76(8jny*mM = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pulley7em4wqj trnns(thc. xvc 6y *;ck1 *g8.)

  A student pulls a box of books on a v42 ch1 v gy/wwcxc08ismooth horizontal floor with a force of 100 N in awgcv hy1/8v2x0 4 icwc 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 smz,d21c5zw kjv :6jq lnooth 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 boo 215jkqzc:lj, n vzd6wks is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is supported by . 2wvz5eu m,aktwo ropes as shown in Fig. 4-2. What v wamk2 z,5.euare the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of / ;4m(q+t0lkb*h79 pkkr g jwmgxphlt0 u*(lvthe traffic ll 7gphkj+l q*m(*khw00b9t mk4v /rux;p t( glight?

  Two boxes of masses m and 2m b,5m7 md0ijta are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is them jb 0d5taim,7 acceleration of the more massive box?

  Two boxes of masses m and 7ie.yi0rxkj ie3/+u. n, .pkgqjt e(d 2lx(sz2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more mas(j e e.ni3pug20 ezx,rk(kdij7+ysq ./til.xsive box?

  Two boxes of masses m and 2m are connected by a rop /d*v-nbizl(o7 d w ye/z*we6we. (See Fig. 4-4.) If the forward force on the more massivwe(d 7 /6iylbo/*w ezdn-zv* we box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by -wff+eb;( (zq vxf4pdu-l7 pd 8bx a,fa rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massive bfqbxe47f f va bwl,z-8d(-pd(up ;f+xox?

Two boxes are connected by a cord running*6o .)olooj n j-yndz, over a pulley as shown in Fig. 4-5. Box I onj)oz6 .-o d*j onoy,lf 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 kincm 0 *up4i4wnwl-+ubfetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force u4p milbnw -wu +0c*f4on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on ww 4n7cbx i*-toood are 0.50 and i4tb xwn* -o7c0.40,
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. It s 3d/t zxd1iiw0lows and comes to a stop with a constaw z/1dti3xdi0 nt 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 horicbfo :tbb r29b rt ;2oxek44(zzontal surface is pulled by a 5.0-N force. A 3.0-N friction force retardsoc92;(o424 tztbx r :bbkberf the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at a)c hn; nauf+l2 rate of $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, a pqx9fh9n .4h;pap3 j+fdy l; bu -vuyk4uck is given an initial speed of 10 m/s. It slides 50 m on the ice be;b fav d4l;n3+.9ju u4qyk py9hhfx-pfore 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 90.0 8.b,iv jw)p yq*s eyk/m longs iey yq*,)vb k/8wj.p. 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.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betwos52*v a.ul pspm/: yveen the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. pm /p .yls :vv*a52osuIf 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 surfacez*+hl4:nfvr abmi5 c 037whj m between the more massive box and the horizontal surface is sm3cjb:+4la v* 5z miwn 7mfhr0hooth 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 fri hak4zgl,,3o 9efc c()c+nnkzctionless inclined plane. The plane is inclined at an angle +(n ,)94cze okcnflhcza 3,gkof $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that y vtrq (0fkv( n/u32ikmakes 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 inclined8o)mjz9. y 1wepvd1:8bp ikga 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 tilted u/eo9t 9*tp2w 3x7s/ggx lrw 3sops(e 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 velocfbm t7x a50jd/;w-trbity of 6.0 m/stw;7bmrjx atb /0-fd 5.
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a mass lgqqegz/ 2;0ba-db(, r/thwk5p pd v/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 rou: l3b1(3/ *xqxnzqv lnxn 4dbkgh $37^{\circ}$ 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 weighinv4-nkg s2 u1/e*o ztq/yedg7ng 500 N along a rough surface. The cable attached to the log makeg2 g7 szndn*uvqe4o-ety/1k/s 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 rougj 3eh .0z6odlgh inclined plane tilted at an angle ofd3h6g.loje z 0 $33.5^{\circ}$ 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. j(9e3gxyt +e1k4wy vfjva. )rThe angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object .xyy e3v+jfaje9vtk( w)gr 14and the plane?