Newton’s law of motion - 无忧得胜-网上国际课程 (5edu.win)

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1#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.36: What happens to the inertia of an object when its velocity is double 5 n:vvptb7y;0buzq8o d?

A. the object’s inertia becomes 2times greater

B. the object’s inertia becomes 2 times greater

C. the object’s inertia becomes 4 times greater

D. the object’s inertia becomes 8 times greater

E. the object’s inertia is unchanged

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2#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

02.14: An intrinsic property of matter is one that does not depend on the qp 5zo mc j9-q;zi,8p8o(wdgosuantity of matter present. Which of the folj o8 p8o9,w qzzo(i cdm;-ps5glowing properties is NOT an intrinsic property?

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3#

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04.16: A 20 kg boulder rests on the surface of the Earth. Assume the Earth has ksit:t3x/qb-bdj f fu;z9mh 44 x0bt2 mass4x 2tiftbx bdbu;9k4f3m- qz0t:/h sj $5.98 \times 10^{24} \; kg$ and $g = 10\;m/s^{2}$ . What is the magnitude of the gravitational force that the boulder exerts on the Earth?

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4#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

09.12: A 5.0 kg sphere is in free fall near the surface of the Earth. What i. w)s nc9t s.p5 28tgrhfxza 1:ijf0qls the magnitude of the gravitational force acti qa8nsrfj9c : 1tst.zhp g.0i)5xw2lfng on the earth by the sphere? The Earth mass is $5.98 \times 10^{24} \; kg$ .

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5#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.09: Is it possible for an object’s1td8s1h e2 zwx velocity to increase while its acceleration decrxz1wt d8hes2 1eases?

A. No, this is impossible because of the way in which acceleration is defined.

B. No, because if acceleration is decreasing the object will be slowing down.

C. No, because velocity and acceleration must always be in the same direction.

D. Yes, an example would be a falling object near the surface of the moon.

E. Yes, an example would be a falling object in the presence of air resistance.

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6#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.11: A certain particle undergoes erratic motion. At every point in its win :u(d34xt6f g5nptk1w5s j motion, the direction of the wg npkx dwf4u:55t (1tj3i6ns particle’s momentum is ALWAYS

A. the same as the direction of its velocity

B. the same as the direction of its acceleration

C. the same as the direction of its net force

D. the same as the direction of its kinetic energy vector

E. none of the above

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7#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

17.14: A block is sus eqweir+2k 5bzd *ew*,pended in the air at the end of a string held by a person. The person pulls on the string uniformly accelerating the block upward for a short time. During this time, which one of the follow+zqwe *r5wbe,kdei2*ing choices correctly identifies the Newton’s Third Law pair force to the force of the string on the block?

A. the gravitational force from the Earth on the block

B. the force from the string on the person

C. the force from the person on the string

D. the force from the block on the string

E. the force from the person on the block

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8#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

07.18: In which one of the following situations ujph er-42 tqz*; vsy.is the net force constantly zero on tq yp.* urztj2-s;e 4hvhe object?

A. A mass attached to a string and swinging like a pendulum.

B. A stone falling freely in a gravitational field.

C. An astronaut floating in the International Space Station.

D. A snowboarder riding down a steep hill.

E. A skydiver who has reached terminal velocity.

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9#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

13.28: An object is in free fall close to the ground.7 p9gd,rt 6rbsv )psuc4d5))jh+ox ga A person intervenes and slows the object uniformly to rest. Which one of the following statements must be true about the magnitude of the acceleration of the object as it is being stopped by the person? The magnitude of the object’s acceleration is a and the magnitude of the accelera sv pbc4d+)6)jsaugtop,g7 5rx r9) dhtion from gravity is g.

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10#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

98.03: An object in equilibrium has three forces, F1 of 30 N, F2 of oaqt-g l)q2dely pnx;, h:5n-50 N, and F3 of 70odneq:,n52p- ;ly aqt hg) -lx N, acting on it. The magnitude of the resultant ofF1 and F2 is

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11#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

01.07: A force of 6 Newtons and a force of 10 newtons can be combine to form a -z7f +ctxu n-/y(d eae7a2ccmresultant with a magnitu-7-z2/+c 7cudaexa ( tcmnyefde of which of the following

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12#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

10.06: Which of the following statements is most closely associa96)w lqekp oa8ted with Newton’s Third Law of 9al8qp6e)wok Motion?

A. “What goes up must come down.”

B. “For every action force, there is an equal but opposite reaction force.”

C. “An object at rest remains at rest.”

D. “The acceleration of an object is directly proportional to the force acting on the object but inversely proportional to the mass of the object.”

E. “The Universe tends toward disorder.”

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13#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

95.06: The reaction fonq vo x8eoidr4-x7 e-:rce does not cancel the action force because:

A. The action force is greater than the reaction force.

B. The action force is less than the reaction force.

C. They act on different bodies.

D. They are in the same direction.

E. The reaction exists only after the action force is removed.

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14#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

14.14: A box rests on 7:.y4aq*.gll +obvg/q3fp o v4lfwzr the floor of an elevator. The elevator is accelerating upward. Which one of the following choices best represents the Newton’s Third Lao.4.ggq o3z l7lf+yl * :arbp/4qvf vww pair force to the gravitational force acting on the box by the Earth?

A. There is no Newton’s Third Law pair force in this scenario.

B. The entire normal force of contact from the floor on the box.

C. Only a portion of the normal force of contact from the floor on the box.

D. The force of the cables pulling upward on the elevator.

E. The gravitational force acting on the Earth by the box.

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15#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

15.15: A skydiver falls downward through the air with constizmwdj.,unnqqkk79gbikn15+8. i *f; bwm, j ant speed. Which one of the following ck9 ,+m ibbk.,q * k1zqj ni;i5gdfjwwnu.8 mn7hoices correctly describes the Newton’s Third Law pair force to the air resistance acting on the skydiver during the fall?

A. There is no Third Law pair force for this kind of situation.

B. The gravitational force acting on the skydiver by the Earth

C. The force that molecules in the air exert on neighboring molecules in the air.

D. The force exerted on molecules in the air by the ground.

E. The force exerted on molecules in the air by the skydiver.

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16#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

06.08: A baseball is thrown by a pitcher with a speed of 35 m/s. The 5lc(b 1(ysnp.d /pv hbbatterswings and hits the ball. The magnitude op(cb s.l1b5hpvn(y /df the force that the ball exerts on the bat is always

A. zero as it is only the bat that exerts a force on the ball.

B. equal to the gravitational force acting on the ball.

C. larger than the force the bat exerts on the ball.

D. smaller than the force the bat exerts on the ball.

E. equal to the force that the bat exerts on the ball.

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17#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

11.13: A physics book sits at rest oe (tt0kl phum02d3l- xn a table. On top of the book is a calculator, also at rest. Which one of the following cep002dx 3lltm-(kuhthoices is the Newton’s Third Law pair force to the force that the table exerts on the book?

A. The contact force on the table by the book.

B. The gravitational force on the book by the Earth.

C. The gravitational force on the combination of the book and calculator by the Earth.

D. The contact force on the book by the calculator.

E. The contact force on the table by the ground supporting it.

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18#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

05.06: The students in a Physicsr)jxfkg z p,cc4*z/p xbq-b ; 1a.g+zy I class were in lab conducting an experiment related to Newton's Second Law. The collected data were displayed on the graph at the right. From this graph, what conclusions c;y1z * rkj-q+cbga 4x ,z )fbpzgp/x.can the students make?

A. The mass of the system was constant.

B. The acceleration of the system was constant.

C. The force acting on the system was constant.

D. The force acting on the system is not related to the acceleration of the system.

E. The force acting on any system will always be less than 20 N.

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19#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.03: If the net force on kbkh s:tc;wc1py(82q +ks,lk an object were doubled while at the same time the mass of the object was halved,then the akk8 ;lck+h,wq b pk1:syt s2(ccceleration of the object is

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20#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

96.15: A car whose mass gv0mrf 1e0yp;6,hgiv is 1500 kg is accelerated uniformly from rest to a speed of 20 m/s in 10s. The magnitude of the net force acceleratin 0m;hg1pygie,r 0v6fv g the car is:

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21#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.05: A tractor-trailer truck qe,qkl*kt b,(hxe1-s is traveling down the road. The mass of the trailer is 4 times the mass of the tractor. Iflkexsh t,-(*qe 1qb,k the tractor accelerates forward, the force that the trailer applies on the tractor is

A. 4 times greater than the force of the tractor on the trailer.

B. 2 times greater than the force of the tractor on the trailer.

C. equal to the force of the tractor on the trailer.

D. 1/4 the force of the tractor on the trailer.

E. zero since the tractor is pulling the trailer forward.

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22#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.16: Which of the following principles best explains,w6t9quj03d b nkil um+ yfl/1 why large tractor-trailer trucks generally accelerate much more slowly that automobilesy w ujm,dnkb6ilu09/f1+q lt3?

A. To every action there is an equal reaction.

B. Everybody attracts every other body in the universe.

C. A force is necessary to change the speed or direction of a body.

D. The total momentum of interacting bodies is always conserved.

E. The acceleration of a body is inversely proportional to its mass and directly proportional to the external force acting on the body.

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23#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.19: A 50 kilogram skater at rest on a frictio; ;1quhxfyu+ bnless rink throws a 2 kilogram b b;;x1uu +qhyfall, giving the ball a velocity of 10.0 m/s. Which statement describes the subsequent motion?

A. 0.4 m/s in the same direction as the ball.

B. 0.4 m/s in the opposite direction to the ball.

C. 2 m/s in the same direction as the ball.

D. 4 m/s in the same direction as the ball.

E. 4 m/s in the opposite direction to the ball.

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24#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.13: An object near the surface of the earth with a weight ofpom+ +vww3e *1 *qxknl 100 newtons is acceleolwk*p1+3 ewxn q+*m vrated at $4\;m/s^{2}$ . What is the net force on the object?

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25#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

98.25: A car whose massw.;e7 faw dam/ is 1200 kg is accelerated from rest by a constant force of 2400 N. What is the speed of the car 8.0 s afa.we/7af;m d wter beginning?

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26#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

98.32: A 3.0-kg block with initial speed 4.0 m/s slides acromzc,* *kcem 2:mj1nk owq)n9 ny5u:do ss a rough horizontal floor before coming to reo*5uw nj *mkm2 e: 9nkyzconc1q,:)mdst. The frictional force acting on the block is 3.0 N. How far does the block slide before coming to rest?

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27#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

95.38: A block with initial velocity 4.0 m/s slides *n0-htbq( pggk5 *cin 8.0 m across a rough horizont gh5 (giq- tc*nnp*bk0al floor before coming to rest. The coefficient of friction is:

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28#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

09.21: A 20.0 kg box remains at rest on a hor1 9y az 3.*7zwz vgyjiam*o1udizontal surface while a person pushes directly to the right on the box with a force of 60N. The coefficient of kinetic friction between the box and the surfac .zmy 937woiza jvz ayd1*u1*ge is $\mu_k$ = 0.20. The coefficient of static friction between the box and the surface is $\mu_s$ = 0.60. What is the magnitude of the force of friction acting on the box during the push?

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29#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

13.16: A block initially moving at 8 m/s acceleratesrxsp.dqwaccudy; 9) 535e jl5 uniformly to rest on a horizontal surface. The block travels a distance of 12.0 m during the slide. Which one of the following choices bestrc55 qc w;ujyad)e .ls59px3d represents the coefficient of kinetic friction between the surface and the block?

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30#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.21: A car of mass m slidel 8:f 8s oz6 (h*hyua;hoa1+lk f0.belv4cjt es across a patch of ice at a speed v with its brakes locked. It then hits dry pavement and skids to a stop in a distanced. The coefficient of kinetic friction between the tires and the dry road is μ . *jv6lh;e1lo8+ ohkuc a: tf 8ah4fb(e0.zsl y
If the car had a mass of 2m, it would have skidded a distance of

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31#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.22: A car of mass m slides across a patch of icbvn rvt-n4f4k:b5 zw;e at a speed v with its brakes locked. It then hits dry pavement and skids to a stop in a distanced. The coefficie4;wkzbvt:5nbv4-r nf nt of kinetic friction between the tires and the dry road is μ .

If the car had a speed of 2v, it would have skidded a distance of

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32#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

04.32: he driver of a car makes an emergency stop by slammi.ku- jcrt*b.s60oi mjv9 o-wong on the car's brakes and skidding to a stop. How far would the car have skidded if it had been travelt u-9wovjri.o0s*m- 6cjbk .oing twice as fast?

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33#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.39: The driver of an automobile must carefully control each of the followinnnba3fjl oz-/ql.-l-fi ;u( d f77 gkwg d 7a lf-gfi/-7k qnonzl3f lwu(.;-jd bevices. Which of these devices can cause an acceleration in a moving car?
(1) the break pedal ( 2) the gas pedal ( 3) the steering wheel

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34#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.25: The net force on a rocket with a weight of 15000 newtons is 24000 newtonsr6cgaa h*xi74 yuatz99cp01n . About how much time is needed to increase the rocket ’ speed from 12 m/s to 36 m/s near the surf xy9ra4ca 06 i1 9ctg7znh*uapace of the Earth at takeoff?

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35#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

07.21: A box slides to the right across a horizontal -,kf;exqf . dh c:)al9 kyhmzg95r3lwfloor. A person called Ted exerts a force T to the right on the box. A person called Mario exerts a force M to the left, which is half as large as the x w9qcd ,fyf )a-5.gle zl ;9hhkkrm3:force T. Given that there is friction f and the box accelerates to the right, rank the sizes of these three forces exerted on the box.

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36#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

02.27: The diagram below shows three roller coaster tracks of equal length. Assub:8,,f-z7dsehi ga cnd ady+ -me that on all tracks the roller coaster carts start from rest at tab ,nz-eyidg7- 8 hfac+,dds: he same elevation and moves frictionlessly over the tracks to the finish.
If all roller coaster carts start at the positions shown, on which track would the roller coaster cart be traveling the fastest at the finish?

A. CartA

B. Cart B

C. Cart C

D. All would reach the finish at the sametime

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37#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

02.28: The diagram below shows three roller b /spj ib/e,2l w y-8/eu8iqkecoaster tracks of equal length. Assume that on all tracks the roller coaster carts start from rest at the same elevation and moves frictionlessly over the tracks to the finish. w /,ky 2 ipbelq//bej8 8us-ie
If all roller coaster carts start at the positions shown, on which track would the roller coaster cart reach the finish first?

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38#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

02.29: Assume the rollercoaster cartrolls frictionlese)kc* lhy1fxmb6r26 s 1p7edq sly along the curved track from point A to p *d7pye12xcs6bh fq6 krme 1l)oint C under the influence of gravity. What would be the direction of the cart's acceleration at point

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39#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

02.40: A box with a mass of 50 kg is dragged ;b 2) mcewjax ynqja j, tj3l0qq:94(zk c*1ufacross the floor by a rope which makes an angle of 300 with the horizontal. Which of the following would be closest to the coefficient of kinetic friction between the box and the floor if a 250 jj0q,4 f( ;qmu:q1kzwace*2 ln yx3j9)jatbc newton force on the rope is required to move the crate at a constant speed of 20 m/s as shown in the diagram?

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40#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

04.40: A 6.0 kg block initially at rest is pushed against a wall lj yngbab+ :j* 6w9o6yby a 100 N force as shown. Thecoefficient of kinetic fr *6a: bnyg6jlwobyj+9iction is 0.30 while the coefficient of static friction is 0.50. What is true of the friction acting on the block after a time of 1 second?

A. Static friction acts upward on the block.

B. Kinetic friction acts upward on the block

C. No friction acts on the block

D. Kinetic friction acts downward on the block.

E. Static friction acts downward on the block.

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41#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

05.10: A homeowner pushes a lawn mower across a horizontal patch of grass withx.k2r 8jt6 j++girkuq a constant speed by applying a force P. The arrows in the diagram correctly indicate the directions but not necessarily the magnitudes of the various forces on the lawn mower. Which of the follkr8kq++i26jj r.g uxt owing relations among the various force magnitudes, W, f, N, P is CORRECT?

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42#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

06.14: A book leans against a crate on a table. Neithe3yn h1q+huxop omk8. 9r is moving. Which of the following statements concerning this situation is CORRECT? huomx+yoq81. hk p93n

A. The force of the book on the crate is less than that of crate on the book.

B. Although there is no friction acting on the crate, there must be friction acting on the book or else it will fall.

C. The net force acting on the book is zero.

D. The direction of the frictional force acting on the book is in the same direction as the frictional force acting on the crate.

E. The Newton’s Third Law reaction force to the weight of the book is the normal force from the table.

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43#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

06.15: A crate of toys remains at rest on a sleigh as the sl6 rfb,yz 6qmqr:1hl(6:iznkueigh is pulled up a hill with an increasing speed. The crate is not fastened down to the sleigh. Whkz,1lz rn6r fq6iqum(6 : y:hbat force is responsible for the crate’s increase in speedup the hill?

A. the contact force (normal force) of the ground on the sleigh

B. the force of static friction of the sleigh on the crate

C. the contact force (normal force) of the sleigh on the crate

D. the gravitational force acting on the sleigh

E. no force is needed

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