Which of Newton's laws best explains why motorists sh1z 2 * e1*ivmlgstccc9ould buckle-up?

  When you sit on a chair, the resula as,n (a x7co.v*rol/tant force on you is

  In the absence of an external force, a moving obt j+aitx yg5gqqvz+ /(sk(p;1 ject will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned o 21j)kt-fyvq nff, whjnq)ftvk1 - y2ile traveling in empty space, the starship will

  A rocket moves through empty space in a straight line with constant speed. It ag n,o x5-vz1ebb3pq5 is far from the gravitational effect of any star or planet. Under these conditions, the forcb15qz3 v-ax p,b ngeo5e 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*) pppy4rk6cny;izzzu . )pc/zio2r) fall forward. You can imply from thici;r p nkpzpz) p*z6o)2ry.4zuy/) cis that the bus's

  You are standing in a moving bu,fzy6n)ry9 (boaj)kys, facing forward, and you suddenly fall forward as the bus comes to an immediate stop. Whan ryyz f6a,)9yojbk)( t force caused you to fall forward?

  A constant net forcesaj g0l gail6 19,k8gp acts on an object. Describe the motion of the object.

  The acceleration of an object is inversely propr)j1;pvy rdu vizv96 (ortional to

  A net force F accelerates a mass m with an acceleration a. If the se oiofd6 a(yk7-3y0 pdame net force is applied to mass 2m-oy0 do7di(e3pkf y6a, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What acceleras ibt jh8; 9 r0z:kqu73h0dqsjtion results if a net force i9jzbqrq :s hkth8su73 ;j0d0 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly awg8j zk+ d vnx:ns/.jy+ay. This is an illustrjxg:++yvjzdnk/ .s8n ation of

  Two cars collide head-on. At every moment during the coll-sk elgt+u7oxkh lgl/tb h6(nf , 5i:3ision, 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 first. Ttkbg - h 3x(5eh:li lnko+,f/suglt67his is an example of

  If you exert a force F on an object, the foeh d: qjis4p*vazv/1v ;)gd7 prce which the object exerts on you widize g;ad*4p qs/v 7j:h)vp1vll

  Action-reaction forc-(nlr4p1i9;r dg fpvwth yd1s5+lvo y8 wjd :6es

  Action-reaction forces ar.kjq m ej.henv 1vq;:8e

  A 20-ton truck collides with a 1500-lb car andwewmuj; 6q6 5sho i*, p.d(zah causes a lot of damage to the car. Since a lot of damage is done on the cahp jdiwme a; q*z5(swu,66h .or

  An object of mass m sits on a flat table. The Earth pul-wy8ot o3(ab yj mrvm1)p9r6s ls on this object with force mg, which we will call the action force. What is the 8rt-oo sv )1j m9ya6pwmbry(3reaction force?

  A child's toy is suspendeda/6roz7qygky9 h j15t from the ceiling by means of a string. The Earth pulls downward on the toy with its weight forcegk7y5qo19zrh ty/j6 a 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 instanta0x utam )eu/sa i:h0u0neous force. The ball hits the bat with an instantaneous force, whumu00esiatu ax:0/ )hose magnitude is

State Newton's three lawehnvehp:ib p0l2, jd um1 e20fjve5 1;s.

  Mass and weight

  The acceleration due to gravity is lower on the 9x.tf q ;.5 k(fpveel(qvm8wuMoon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surfam.ul;( p fqv.tx9fqwe5kve8 ( ce, compared to Earth?

  An example of a force which acts at 1.i0w+f*b;4n ihg+ ymdzgqawdbo0iium 2 9:o a distance is

  Who has a greater weight to mass ratio, a person weighipla p93+ r ba/k-0zpuxng 400 N or a person weighing 60 l9u/x-pa3p+pab0 z rk0 N?

  A stone is thrown straight up. At the top of its path, the net force w*x)mhg e-+ 3k2hoiphacting on it isxheik p 3*-)h+ogw2 hm

  A 20-N weight and a 5.0-N wei h n(mjt(qd)fnctw e0(*3k *hrght are dropped simultaneously from the same height. Ignore air resistance. Comtfwjkh0d(*mh)3 (*r qtec (nnpare their accelerations.

  A brick and a feather fall to the earth at tb.tbbi ;gl,1their respective terminal velocities. Whict1bb,g l.t ;ibh object experiences the greater force of air friction?

  An object of mass m is hanging by a string from the (: x1rht)0we.dnl*yij/o wob ceiling of an elevator. The elevator is moving up at constant speed. What is the tension ib0x1o(nti.h w )ywd :/l*roejn the string?

  An object of mass m is hanging by a string from the t;rj aj+.u .hlceiling of an elevator. The elevator is moving upward, but slowing down. What is the tension in thejru;+ha.lt j . string?

  The force that keeps you from sli6mt9()zw y adlding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is to keep a3- /eoipp ewjuus5l*r9 p8k3pushing it with l/uw 9k3 epsrieoj- p3u pa8*5constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (oqbi( :8h o-- nhtprd2friction is present) at a constant rate. The experiment is repeated, and api htbn2oo (q hr:--d8ll 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 inpa51m :cx .dapclined ramp at constant velocity. Thus we can deduce a5 dm:x. cpp1athat

  A block of mass M slidzk q68dsl 0v6ges down a frictionless plane inclined at an angle q with the horizontal. The nork vlgq0zs668d mal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angan8kie0 jek 28le q with the horizontal. The normal reaction 8nak08ji2ek e force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane incb b (k17seq:*;rhfd1 kg(md sqlined at an angle q with the horis:rh( (befb1mk1k7g *qq;dds zontal. The gravitational force is directed

  Two toy cars (16 kg and :ve4xwpx5h 51l(eb, 2 rs9ynjfe eb,v2.0 kg) are released simultaneously on an inclined plane that m :l55pberv,e,hje sy(e9412 xfwbv nxakes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is appli1m57oh lbwai93l )xarp r 3 ct6w,sb:led to the object, and it accelerates atb6b:r,sp aow)cahwm35 ll9i3x1tr7 l $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in b4 :d(dj-lh,o5az cy g7.0 s. What (hzbcd:oy4 -dl,a5gj is the average forward force on the car?

  Starting from rest, a 4.0-kg bts yt*q.j b(s9ody reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting y q(sjs.*9btt on the body?

  An antitank weapon fires a 3.oy6l 3zf+ 6t4ro*go pkkl+7i d00-kg rocket which acquires a speed of 50.0 m/s after trp+o7*t r6lzil36k 4o+do g fkyaveling
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 10g :7txuxex )+s-kg mass from resu t ex)+gxx7:st,

  What is the mass of a person who 4hus7qc6p guhdueo)r ydt84ibi,7+/,u h re .weighs 110 lb?

  What is the mass of an objhprhg8-n;3bm ect that weighs 250 N on the surface of the Earth where the 3pb; h8hrmg- nacceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the object on t(de q8(b*w+nnmb /o (h6dvo zphe surh (+6 8 vzb nq*p/bwde(no(mdoface 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 objejmybj enut21am.xwy;,7t o;8 ct B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compar7m.1,my otxnj8 ;2aej;buyw te the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite e85 f;f :wrs,(abpk:b.hixfmp.e;dk 4gq3k hlnds of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope fm, hx.k; f(d3w8bkp;: 4:kl5g are.bipshqfaccelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F act:lfg*vry9 fb+ fb :es3s on the stack, and it acceler::bfls9 fve*3+b r gfyates 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 will the s;. ujj qk*bcrd9l )f6jcd2d o,cale be reading when the elevator is acceuor jdd* 6 )jqkcdfl,bc2 .;9jlerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in a w. zaon utkvq16ue.-6xvwj0: n elevator. If the mass of the person is 60.0 kg and the elevator accelerates downward with an acce.-0vtv6uxw1 k6 wa ej:n qzo.uleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an el ceym yr5t n(*5z+rf(mevator. If the mass of the person is 60.0 kg and the elevator accelerates upward with an acc eyr 5t+5mzcr( n(m*yfeleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a r ltk.q9-;di,p243evcwl p rz5.0-kg mass. One force has a magnitude of 8.0 N and zv- p 34;pcw2e qllkd.,irrt9 is directed due north. 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 truck. I u+:nvxq , , gcy,l*fpk5ywrk8+iewaiu z8 k-0t is held in place by metal brackets that can exert a maximumuew -*,p,w5yrq+, cxl8+f:k kn8ikg zi0auyv 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.j)4ap.z 8awk s ;pph-mt8w8af 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 stopping time if the load is not to slide forward into the) w8fs p mwp8;-pja8h4.t akaz cab?

  In the Atwood machine shown in Fig. 4-1, ifk1y+klc x:d :p98mucr M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass om8+k :p1ukcx :rlydc9f the pulley.)

  In the Atwood machine shown bqxt/na0v8x1 in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? t/aq8bx1v0 xn(Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth hor ;:z1g0rrt4 gwpzqj5tizontal floor with a force of 100 N in a directr15jrtz;w :q 0zgt4 pgion 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 horizonta*ia2 :yajm4o-, 8i fpxbzcv5nl floor with a force of 100 N in a direction of 37.0e above the horizontal. If ix2c p*ya :5fab -i48m ozn,jvthe mass of the box and the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weilttaq 9p7+: b4/0iqqgnfzrja i r;95bght 100 N is supported by two ropes as shown in Fig. 4-2. What are the tensions in the ropes?iqnp5i9/gabtq arj;z t0qb 4lr9+7:f

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass e, ygm ey4roe1n8ykf.onf7bk 29df8+of the traf7rne2fk9ogkof f,dme y yy8n81+4.e bfic light?

  Two boxes of masses m and 2m are qcrxc.19e( gc in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more massive box?1q(erc.c gc x9

  Two boxes of masses m and 2m are in contact with ez : m6 1dju+tm8iyvwm:ach other on a frictionless surface. (See Fig. 4-3.) What is the neti m86ymm 1: vu+:jwdtz force on the more massive box?

  Two boxes of masses m and 2m are connected by a+q*yotjw (fj(+ g re)hmnjy( . rope. (See Fig. 4-4.) If the forward force on the more massive box (fw + h)m .jr+n*yq(jty (eojgis F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-2ksobrj*-)gcx(w9gl )ip* n t4.) If the forward force on the more massive bwkbpgsr(jl-c2 * x*o9i ))ngtox is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as s2ro yef;):+jueq sajp*9:nf xhown in Fig. 4-5. Boo up2fa s)f *:rj+ex:q9y n;jex 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 frictions between a 3.0-kg box and a dehxqe82r -. e* 3jkjufxsk arefehur3q-8x .*xjej 2k 0.40 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 kineticg/*y7 1tq7ova35u kxi ) 26hgojmvsma frictions for plastic on wood are 0.50 and 75ykhigm 17g/)jo*msvav6uo 32qa t x0.40,
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 mo- 1lot.h, ly+x direction. It slows and comes to a stop with a.th1 l l-y,moo constant 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 a4ic6f1 *.qcz xd svqh25wtas 8 horizontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards thewqs f 65t*c . iah8d2vxqcsz14 motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest8bxd5hm 45lql , at a rate of $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, ggdo9m bv .1shk7j4) ea puck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficm )ogh74. gd e1kj9svbient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, policem1,8qp3kbvkvv(sfa8*w in u, find skid marks 90.0 m long. 8 mw*kv 1safqvkv(n,pi38 , bu 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. (Sey lzu;44uztbi.1,t kbe 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, 4l k ;b1z4yitz,b.t uuwhat is the static friction force on the less massive box?

  Two boxes of masses mqup5s5y y t+kw37x0 dd and 3m are stacked. (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, wyq 50u dk3+7w ydsxp5that is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is inclined7eqfdx p;3ign ow+mq)37m j k7re 1-ze at an angle of )rkwn 3g q77 1id;+em3 xpjef7- qmzoe$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat1z)/ wu9p6dg7tay fgo hill 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 sj3(xlrexhk (v m+ + tv-7-nxmangle 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 at z7aem ;it5hk 07bis4-bjzj 8k 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 inclintx:v to9ex 23ded plane, at a constant velocity of 6.0 m/sxott 9v:3exd2.
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 roug9fwx0g k ;h30b5ftlwkh $37^{\circ}$ 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 a5p, awmy3,2 r1m2kac,bjxyel 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 logoa.b (oas3: yi weighing 500 N along a rough surface. The cable attached to the log m s 3oba(i.oy:aakes 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 plathddnuly /dy5447+w1;khdb k emlk21ne tilted at an angle nlb;k5 4khm1uhd/dtwk2+7y 4 d d1yleof $33.5^{\circ}$ 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 incl y )(elptidp/5ined plane. The 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 and th) /ld iy5eppt(e plane?