Which of Newton's laws best explains why motoristsmqau8. )wd8hyvps.(z should buckle-up?

  When you sit on a chair, the resulta, csl::+gfzi ce;w roqo2o a,pto+8k+.mjw4dnt force on you is

  In the absence of an external force, a moving object will,mz2403,fizpzne ank

  When the rocket engines on the stars73 mdgrg dwp)m)wt,,thip NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the starship r )dtg md,mgt)w3,7wpwill

  A rocket moves through empty space n )onn+j+p7f q+to-n lin a straight line with constant speed. It is far from the gravitation o o +jn-fpnnnt7+lq)+al effect of any star 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 moving bus, facing forward, and you suddenly falle6z9iqg )*7 wbw hz f19xvop*p forward. You can imply from this that the w)x pfh9pi*g6q7z b91* zeovwbus's

  You are standing in a moving bus, facing forward, and yoyk /yrw(m-5ol0opy0)7d ;j dk v6ajngu suddenly fall forward as the bus comes to an immediate stop. What force caused you to fall fora;y/yogdm5 ( r0kdnj)07kyvwolp j 6-ward?

  A constant net force acts on an object. Describe the motion of the o y(ogly 4 /q5,atajiaah4 9gf;bject.

  The acceleration of an objeog2w fn:jlpi k. izj2s2 e 8u;boh3j90xp j84act is inversely proportional to

  A net force F accelerates h e,7 qsv5k/jj4u0(dwtvb8c pa mass m with an acceleration a. If the same net force is applied to mas ,5 8d/cv 7h(tbwqpu 0j4vkesjs 2m, then the acceleration will be

  A net force F acts on a mass m and produceysm.:m6koq. ewr9s +zs an acceleration a. What acceleration results if a net force 2F acts on mass9y. so eqz.r+mwm6 s:k 4m?

  If you blow up a balloon, and then release it, the bal2sv0hm)e-y 7eq j5l-ma zr v6ploon will fly away. This is an illustration o2m5r0mpel 7-v6jae-hq)z ys vf

  Two cars collide head-on. At every moment during hntzw9n xg2wt3/t3k* q 3g3vjthe collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of t/3gw*nzxwthvqj3nk2 t 3t3g 9 he force the second car exerts on the first. This is an example of

  If you exert a force F on an object, thsm s/n+w*ul +q45b b.tpnnpv+e force which the object exerts on you wills/5nppsn* +wb4 v qln++bu mt.

  Action-reaction forcestuyi vr6;o1i 4y cur h839cop+

  Action-reaction forces arb 2ctooh76-v he -.myse

  A 20-ton truck collides with a 1500-lb car and causes a lopy ,m:l nhl:z) +;fmvwt of damage to the car. hzyn fwll:vm+;mp) :,Since a lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on apb9j1-vvq+o )ol; jpthis object with force mg, which we wil)pqvv1 oaj -jpo+ ;9bll call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means.s,rrs.eq* fc of a string. The Earth pulls *,se csrrf.q .downward 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/c e5fpi1u 9*6k 5xy xyehctb+ force. The ball hits the bat with an instantaneous force, whose magnituiy*+ pbc5/h6x5 uc9fex1key tde is

State Newton's three l ;97fn;xzhdi vaws.

  Mass and weight

  The acceleration due to gravity is loweu.m45as5l k g4e6xjxo.nq 6ter on the Moon than on Earth. Which of the following is true a lqg66uee.x ms4tj54 .ako5xnbout the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distancefk7iwfkw8 /7j is

  Who has a greater weight to mass rs-uj;5aah g/y atio, a person weighing 400 N or a person weighingu-sjagy/ ;5h a 600 N?

  A stone is thrown straight up. At the top of its path, the net force acting/ u.3)dk azdl2jdri+05kve fi on it ziu.ak2 r+/divd efd05jl ) k3is

  A 20-N weight and a 5.0-N weight are dropped simultaneously fromgaqnn *mwk 85 a8(2)bassu4ktjn) 5z o the same height. Ignore air resista)*(4 ngksjz5 tua q8nsa)82kwnab5m once. Compare their accelerations.

  A brick and a feather fall to the earthic9 vk.puu l9.q+1c.k9s bmlp at their respective terminal velocities. Which object experiences the greater.ps9u lb.v+m99l. ukcp1ikcq force of air friction?

  An object of mass m is hanging by a m 7dn3k) v-yg*9zc -cevn9bj/hjdd3r 49xa im string from the ceiling of an elevator. The elevator is moving up at constant speed. ed*d h)vy 4 x-n/nviz-kg jcm3 ad99j cb9rm37 What is the tension in the string?

  An object of mass m is hanging by a st-e6u )ul t sqobb,4v5bring from the ceiling of an elevator. The elevator is moving upward, but slbqu 54b,vusb o -6l)etowing down. What is the tension in the string?

  The force that keeps you from sliding on al1n;eyw1vpu.g/vd7 mn icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is to keeo;3 0 9qolvderp pushing it with coo09oerq lvd; 3nstant velocity, because

  A horizontal force accelerates a box from rest across a horizontal l tzh7xb406vksurface (friction is present) at a constant rate. The experiment is repeated, and all cond4kzvh0bl7t 6 xitions 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 velon6 zfzz;u92x5 9qebwfcity. Thus we can dedxuq9 ;e 2zfznz5bwf69 uce that

  A block of mass M slides down a frictionless plane inclined at an angle. jo, hn j0m nc9 tl1a3qpmwh-en8b0:t q with the horizontal. The normal reactio tw0cnl -hjmb:he8n30p n1t ajmq,.9on force exerted by the plane on the block is

  A block of mass M slides down a mt+a/ 6bjf92 dfxdp b8frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted ba d9/dbj xb 6ff2pm+t8y the plane on the block is directed

  A block of mass M slides down a frictionless plane incib d.q 4cawnd9ag+z8)lined at an angle q with the horizontal. The gravitationb qidac+)waz n89d4g. al force is directed

  Two toy cars (16 kg and 2.0 kg) are released simdt8 ef 2jdmu *7dqh0(wultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration aftdju7m*0 eqhfd w(d t82er being released.

  An object sits on a frictionless surface. A 16-N forczjjvv,x2f x/ -tll40 b .-xmc6rwmw .le is applied to the object6fcxbjmw lx-.0 xvjr l/m-lwtz ,24v., 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 8( zh+e 2se:8gh-m4 2h h .bwkckdtokhfrom rest to 27 m/s in 7.0 s. What c2w+4bt oe es h h- 82(kdkk:.hhmhg8zis the average forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed ouj on7ivwj+t k,n/)rbd6n ; (of 8.0 m/s in 2.0 s. What is the net force acti)/von ;nj, wu 7ob(6dtikrnj +ng on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 5: gmatlri1-k(5tdc 2(orl -nm0.0 m/s aftercat- l ( od- g1i2rrn:lk5tmm( 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 zw-uh 6bqzan8a+/ fonqy3 u-:a 10-kg mass from rest,ay/u :-n f6 hu8ozqnb-a zq3w+

  What is the mass of a npqt n9d35r2c)kvp * iperson who weighs 110 lb?

  What is the mass of an object that weighs 250 Nq, - /afj9dxlw on the surface of the Earth where the acceleration due to 9wl/,-jfqd x agravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the object o8 n- mrefa6:xnn the surface of the Moon where the acceleratian f6e:-n 8rxmon due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, 6n* 7dht7 v10rra :xuvyx+6 ,ghpqorz and object B weighs 40 N on the Moon. The Moon's gravity is *h+q ruxryxg1avr7 o, hd7n:zp 606t vone sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-/d2zsv39: ii g7ygzttof-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's fozs9/d7gitg v3zy: ti 2rce if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F acts onl: up.,rx5nen+*s3y5wmr /.gn5 fq 2rfwdq k v the staw2fu:f q ,./eprv*r n+mskxy3r d55qn nl.w5gck, 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 scale in an elevator. What wildiy7 n6yr( :ovl the scale be reading when the elevator is accelerating downwar6(yn do:ivy7rd at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60o(by6ht*s9.7bwi 2a wmq+yzx .0 kg and the elevator accele2 i.y 69bwt o7wmqyhzxa *(s+brates 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 / v+na8 hr4yxn52 sowk60.0 kg and the el82 5wxo 4a +ysvnr/nhkevator 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 has a magnitude of 8.0) b 5 ysau. rg/yz,no8z,-qshy N and is directed due northzs.yy sagq,8/z,runyh5b-o ). The second force 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 t u*/2fs 1rbquaruck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the t fa*ru/1bs q2uruck 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 m6ynpejc1d 045l+ hj jflatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontalc 5ejj dmlhnp16y40+j 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;8k(jsqsv 0w i, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the vj; (k8ws isq0system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg andl)rf i n*v6esk4 kz/mu4zp( 2y m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of z 6 krnly(kim fpuev*/4 s4z)2the pulley.)

  A student pulls a box of books on a smooth horizontal floor with .*wqgtcg53u ta force of 100 N t3*5q.cwugtgin 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 ,et21 prci 7)zgi6 +tl+vtfq msmooth 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 is 40.0 kg, what is the normal force on + ri1tif2 t+vlpgq7mz), t6ec the box?

  A traffic light of weight 100 N is supported by two ropes as shown in Fig. 4kw/v 53+ i2sa grl(9ci9mvmgt:e+oq s-2. What are the tensions in the 2ricgv qmv ae9w i3/9+s(k:t5l +ogs mropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, whatw*b h,m6iskx: is the mass of the traffi 6ism kxh*:wb,c light?

  Two boxes of masses m and 2m are in contact with each wk0+f4* vy nniother on a frictionless surface. (See Fig. 4-3.) What is the acceleratnvy 40fni*kw+ ion of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionlessluf/y:ziirf:.j nr9; surface. (See Fig. 4-3.) What is the net force on the mor :yij9u/rr:; nzlif f.e massive box?

  Two boxes of masses m and 2m are connected dz ju;mft,r1z j,aa;5 by a rope. (See Fig. 4-4.) If the forward force on zft; jzjumr1a ;d,,5a the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (Sg(270il2 fqnpe f0wsb( i* xvsee Fig. 4-4.) If the forward force on the more massive box is F, what il((g 7 0vbpe22i*0wf fsxqns is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in Fiq44rsoqh,v3++;nm qy srwdj9 g. 4-5. Bvqy,wr4jo3q4d r+;+mhn9 sqsox 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 o84i7 p7im; ocanpf n/ 0*anmwfrictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on thno7aci mf/np8p0am* no 7wi4;e box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic n)y0q hkz:ldw, /mf/a- af 8vzfrictions for plastic on wood are 0.50 anf8 z-anlwkdqya,z/v mh ): /f0d 0.40,
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 slows and comes ;wotu)rq(xhr nb99 w( to a stop with a constant accelerh tr(nuqr(xw9o) ;9bwation 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;y4gwzs c75tubcxxf9q d;w:5 3.0-N friction force retards the motion. Whatq: d;fcubxx 9zwgc4ts57 5w ;y is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from (fmlu2 f.4 lkprest, 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-qea k6)54bzv 88qw7gcl bzc w of 10 m/s. It slides 50 m on the ice before it stopsk8wlqe4a-)6vbzgc bz8q5 7w c . What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid/(5b;pn dh jdb 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 the speedbd(b d/pn5;jh of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface between0etvfb kj2x s 66ygt89 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 sbs6gek f9vj 26tx0ty8 lide 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 surface betwdmg-83 vcbm*lyj(vtau2e: 2i 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, what is the coefficient of static friction between the boxevc8(ym- ej a*iuv t gld3:2mb2s?

  An object is on a frictionless inclined plh asy6ln:sk 3;j5nf8x ane. The plane is inclined at an angle o8n:f hs kxjl6syn3a;5f $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hiljfi,, gn -v7vrl 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 plane with an angllg5/vo 1e x 4kpe6cax3e 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 q.)ov ro6v8gvinclined 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 djhzdp +2g(kd ,irectly down an inclined plane, at a constant velocity of 6.0 k(phd2gz+, jdm/s.
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a mas)uc / ghjkei;k3 ug-0js 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 roug 4 wvi*frp49(uj 1lzjlh $37^{\circ}$ 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. Th7h8s5q0dfbsyn 02 6 hul zlju(e cable attached t(5f u 7db 0u2z0y h6hslql8njso the log makes 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 inclined plane tilted at agj54dz eyoz7ls5xpws a5( o6 s)uos/0e3i:mh n angle 67zop4yds )u0mo ow :g hszs5jl3x5 (a/se5ie of $33.5^{\circ}$ 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 gradual z8wmx5 n4mvndc.jj,vhx0/ -mly increased until the 8jnvmch. x,/d 5nx40j mw v-mzobject begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?