Which of Newton's laws besqu,0suo7l1 rjt explains why motorists should buckle-up?

  When you sit on a chair, the resultant force on you i gufrt- ddsm6h,il c5ud2r;7r/;*n2 jb 9cxla s

  In the absence of an externa xnrekr ic-.o41ft1)a v j,foi 3blv3-l force, a moving object will

  When the rocket engines on3k+v/l*ytqq- c j je0e the starship NO-PAIN-NO-GAIN are suddenly turned off, whil qcvejql03* t/yej+ -ke traveling in empty space, the starship will

  A rocket moves through empty space in a straight line with constan b818 rs zcgtyk(9:1oebll g2qlod:: rt speed. It is far from the gravitational effect of any star or planet. Under these conditions, 9l:by1zdtlrloro(e 8g g8k q2:sbc:1the force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving 9x+xp3,ouwf;zhn;z fbus, facing forward, and you suddenly fall forward. You canf3x;9+;fnzu xoz p,wh imply from this that the bus's

  You are standing in a moving bus, facr:ptcr-i ,2 foing forward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused you to fall forward?tc,or fp: r2i-

  A constant net force acts on an object. Describe tz6t xf(y7ryuztuq0jd2-z b+ 8he motion of the object.

  The acceleration of an object is inversely pro).ont(9n vldu:3xllo e tde)4portional to

  A net force F accelerates a mag h+jh7tbinsl1 r)9w /ss m with an acceleration a. If the same net force is applied to mass 2m, then the achj 1+g/ni ht9wlsr )b7celeration will be

  A net force F acts on a mass m and producqf ek- *r9-ih oj pk4o:a-2mxoes an acceleration a. What accelerationoe-o:pkj k*fam2h- qr9ox4 i - results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then-jb.pf1q 5or*cvb frl 2(;uzk release it, the balloon will fly away. This i;5* -fofvbrjuz1.kpl qr 2b (cs an illustration of

  Two cars collide head-on. At every moment durig j2e;q cel)1fng 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 exerts on the ; 2qfelg 1e)jcfirst. This is an example of

  If you exert a force F on)b 5a6nknixs;yo6 +xw an object, the force which the object exerts on you wiliax; +osnwn6k5) xyb6 l

  Action-reaction forcesonb kqop l/el52xk7;:

  Action-reaction forces a*tw ic22a 4xkhre

  A 20-ton truck collides with a 1500-lb car and causes a lot f+ryt.zn 8bipw68l 2ci -d7huof damage to the car. Since a lot of damage is 6z+ l b-pn7udch wr.t8fi2yi8done on the car

  An object of mass m sits on a flat table. The Earth pulls on tsm.v6 ek-urt-x+)63q zmjx7 brsa -h this object with force mgt +-tv mzqx-b6s7-sea.)rxu 6k3 hjmr, which we will call the action force. What is the reaction force?

  A child's toy is suspended from the im mc*rx;(/ 1psepwnoa ;a 76nceiling by means of a string. The Earth pulls downward *mep n/ ;si a;mwra1(7cxnpo6 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 instantaneous fba0y5x. q2xb qy-z 4ndorce. The ball hits the bat with an instantaneous force, whosqbq0 ybxy2. 5naz-dx4e magnitude is

State Newton's three )u gc *sm.1h dy5*7 vuu:p-sgh*kygzz laws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which ok,6 tx4r)m ohdf the following is true about the mass and w txk,4 6mr)ohdeight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts x+oz x 3 db3q.yu6).zjya-z kxat a distance is

  Who has a greater weight to mass ratio, a perso:4bkqlgg, c87ga9i ssm t6-arn weighing 400 N or a person weighing g6 sqal78gmg r: a-,k btis9c4600 N?

  A stone is thrown straight up. At the top of its pa*o*ke:zr zh57nri 1jf wn)7lqth, the net force acting on it oz e)wn7qzik :1* rfhlr*j7n 5is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the samh. r-nw,n06sq ,9tib dc)jfdfe height. Ignore air rejd0rqt,-b 9s, nfd6w)hc .in fsistance. Compare their accelerations.

  A brick and a feather fall to the ear:,a qhqlp3 bn0 u f4uj3oxd) jenfg ,/.4qp3fvth at their respective terminal velocities. Which object experiences the greater foru0/,db aj n3fvh. 4 e3qo:qpjnpuff,4q x)3lgce of air friction?

  An object of mass m is hanging by a string from the *,hsfl,f):l e( mcoz.l9xnne ceiling of an elevator. The elevator is moving up at constant speed. What is (m ,s,9:l.ez e)ncn*fohx fllthe tension in the string?

  An object of mass m is hanging by a str j 8 q x6y:(pu)vxdvtjo4g6j:ming from the ceiling of an elevator. The elevator is moving upward, but slowing down. Wha jgxj 6dqm :v4u(vo86t xp:)yjt is the tension in the string?

  The force that keeps you from sliding on ajd,ozl g(- lc,n icy sidewalk is

  It's more difficult to start moving a heavy cartow 5+hn /nz +s3v 0fjcvf1aejo(n from rest than it is to keep pushing it wisw haf/01jcf5onn( ev z3+j+ vth constant velocity, because

  A horizontal force accelerates a box fromr s2.x8trx 5:9ekw xan rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remxwx5 .r9re:sxn2t a8k ain 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 a- z o157x1 vlvl/jp0 hg a,;ma jm::gsrod0aoct constant velocity. Thus we can deduce tlj 0 :5ragvh :l1 a/m,osp7c-0;g jz1oxdmovahat

  A block of mass M slides down a frictionless plane inclined at anpjy2x a; o0/wl angle q with the horizontal. The normal reaction force exerted by the plane on the block20;p /ljxya wo is

  A block of mass M slides down a frictionless pla n6s1 o;+1wzeyna ffdz5zx54yne inclined at an angle q with the horizontal. The normal reaction force e1so +5x ;neyyzfzn5 zfwa61d4xerted by the plane on the block is directed

  A block of mass M sli1u80itwczu j*ty.yqt h-4gp:des down a frictionless plane inclined at an angle q with the horizon10qytp:tu8*i gtj uh-cz4.ywtal. The gravitational force is directed

  Two toy cars (16 kg and y,t:jpr wi 1t( bry yfshnb)-8 .3z)fp2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being releaser8(pb)p: bh -,tyt3.snzf iyrwj 1 y)fd.

  An object sits on a frictionless surface. A 16r pr w5.z.0 tm8dzj ou9g 3s5co+gxha5-N force is applied to the object, anp90 5+dcrga j og8r5 zzw..5tmhos3 xud 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 rlp;m; pal,z q;hn:/dt7 e(ra aest to 27 m/s in 7.0 s. What is the average forward am7;td/;p l h:ql,aearp;(znforce on the car?

  Starting from rest, a 4.0-kg body reache3cyzw,ur(zhq *0y *dq s a speed of 8.0 m/s in 2.0 s. What is the net force acting on the borwy* q yuzdqc*(3z h0,dy?

  An antitank weapon fires a ;u 44fxgta rnofhr0:-ys .;r w3.00-kg rocket which acquires a speed of 50.0 m/s after travelingyf4rroa -;04rs.wgn;h :xuf t
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 masqeq-rp; 6judu:9nke9 j9e2 jolx+uw3s from rej-e +dq 9eopj l6uux;qr 93nj2wue9:kst,

  What is the mass of a person who weighs 14a;b.pngc o ppiu-wh,w o a *7/w4hb7w10 lb?

  What is the mass of an object that weighs 250 N on the 3-y/.sjxtye)v u,5adk: :cuqpnbfi1surface of the Earth where the acceleration due to.fa-texuin 3: yj5 sv:upck b,/)yq1 d gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of thed;9wv:mabptm4-.w dds*o:h w object on the surface of the Moon where the acceleration due to grav; am:odv. dw4: mb 9h*-pwdtwsity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Eartcnf n 80(t f1djuphv)2h, and object B weighs 40 N on the Moon. The Moon's gravity v n82 dufn1ft)hp0j(cis one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-. c4ct ft,mfpsh0z hdu/sl4 2,war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's ht ftpsfczcm .u sh2/,l0, 44dforce if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force4jkk8/6rus t scz1qg9w2t ow; F acts on the stack, and it accelerates tsojt4q w9c81u wkk/6; gzrs2at $3.0 \; m/s^2$. 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 hrmi1ms 1 :ss8r z+te+scale in an elevator. What will the scale be reading when the elevzrth r+11:se sms8mi+ator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of thp)t 0 rc(qxdrw5 1*urge person is 60.0 kg and the elevator ac1pcrt wq5)d*(r 0x rgucelerates 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 60.0 kg.5 yp (xka(n.pq v:o8swc p;hi and the elevator accelerates upward with an acceleration cxpqo. ;a.pn i k(whvy8:5p(sof $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kgtdj;r-s*z) h c mass. One force has a magnitude of 8.0 N and is directed due north. The second force towasdzht)* cr j-;rd 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 is helmxo:moitk-l +mtul+sq 1 5 .*s8i7 ychd in place by metal brackets that can exertic. ysmkxo1 +hs:5 qtmlo u*- 7m+8lti 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. al2pq)eg1 h+o 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 stoppin1 2lepa)gqho+ g 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 anh0w g*p 7vin:qd m = 0.40 kg, what is the magnitude of the acceleration of the i:qh gpnv 0*w7system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.6hof9/odqs(1b 5hg ss10 kg and m = 0.40 kg, what is hfs(ohs9g q5o1bs /1dthe tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a boxswwh7a -y1 crqz: *he- of books on a smooth horizontal floor with a force of 100 N in a direary-1ech-*w :qshwz7 ction 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 b ;dq2cr jx38wk ;dbfy8ooks on a smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If kd;bx yr2fw8c;38jd qthe 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 supported by two ropes a8zya 5(.qc1u z, tn-pss d-hrms shown in Fig. 4-2. What are qu5azs-mns8d r1pz yc. (t,-hthe tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what/ sg 7y/vxg0ioi5s r8o is the mass of the traffic s8xos/govgy57 ii0r/ light?

  Two boxes of masses m and 2m are in contact with each other on a frictionu99fr 8y1v2jpuv4 nw nless surfawu9pu12jy 4n 9fr8vv nce. (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each dl5q;(ho u a5e7k9zd cother on a frictionless surface. (See Fig. 4-3uq 9za75k d5e(od lch;.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connecg4k+a+; ri,h qjt sc*sted by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, h;cks+t jag*+,rq4 i swhat is the tension in the connecting rope?

  Two boxes of masses m and 2m are connebs) xnsk.guf7 fbu5,t3dwm6/ 3a * fjlcted by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of taxf3jfu 576 bsn3m,s. )d*bulftwg k/he less massive box?

Two boxes are connected by alj inm) m(4n0n cord running over a pulley as shown in Fig. 4-5. Bn mni nmj(l4)0ox 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 frxkin n-b;-h - v64ajdwictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 -vbixnnh wda -4-jk; 6N horizontal force is applied to the box?

  The coefficients of sta-4 qhqvhtl8+ xtic and kinetic frictions for plastic on wood are 0.50 and q-vlhx4+qt 8h0.40,
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 surfe-vk;5cigt dob( jfnz-s-eb5f .: v. uace in the +x direction. It slows and comes to a stop with a constant bjkicbv.:eod-f-;5 f(5- nst uz g. evacceleration 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. 6 :sty0tg8b:xj m9zyu71q/w l, bzpq1rfbuu6 A 3.0-N friction force retards the motion. 6 ub8679ztsqfyl/p0: :b1,ztw jg xuru ybm q1 What is the acceleration of the object?

  A horizontal force o zlonf1lxo-2bwp(a5o3 5+zwt f 5.0 N accelerates 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 ptrf7g8cnz f7 k,c8bqyat3 v(1uck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic fri3t 1vy8akft, n7b7q(gz8 frccction between the puck and the ice?

  During the investigation of a traffic accide.) dh)oxnpdsb; pu- u:nt, 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 cx))p :h;un-sdodup b. onditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) jpb.;thx0-no0+uy pb 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 d;u+ -p jxyh0ntp .bob0oes 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 surfa xrw,n;ytn 8(ynw i5*lce 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 r yn i5 ,xnwt8n*(w;lybox, what is the coefficient of static friction between the boxes?

  An object is on a frictionless iw39bmf:in5g znclined plane. The plane is inclined at an angleimn9f3g b 5:wz of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill j 8du, ;f+nck;uc a9mhthat 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 plane with an ang2 4d.1lzr/gxgo2fclnvez2k z2axk +- yzv/, u le 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 smoothy3s c(+hwla p ;xs3nt;o pz*3c inclined plane 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-z-zrp 9en d,q velocity of 6.0 mq z-der- 9zpn,/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 down a aolh:ihnw8x 9kpf 4+) 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 masayb ,/iei*z3r+ y8blf s m slides 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 weighi*pk3 ayjl ; cej,5:dtxng 500 N along a rough surface. The cable attached to the log md 3*yljc: kp,jetx5a; akes 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 rah*)om;m 7 k; 9ahjtxiest on a rough inclined plane tilted at an angle ofj9k a mo ;th*i7mh)ax; $33.5^{\circ}$ 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 indf;h e x uw:/)51 ;ovamrk7kiycline is gradually increased until the object begins to slide. v7w/: u1xh;mkf5 yi a)d kore; The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?