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

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1#

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99.36: What happens to the inertia of an object when its velocity is dokx4qir*q,ya )p .1apc ubled?

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 tha mk)v sb5dw4.ot does not depend on the quantity of matter present. Which of the folbk45vo .)d wsmlowing 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 /7)(t6esfo55 vte*qnd umx+ ruh c(pz mass s tofuc+/z utdhe57mn(5v*p6)qr(e x$5.98 \times 10^{24} \; kg$ 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 ofvm6 bn(h 3h1of the Earth. What is the magnitude of the gravitational force activm3 f n6hbh1o(ng 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’s velocity to :+-qt .hhen v5*nkci fincrease while its acceleration decreas:e+- ni5.h qfktnc*vhes?

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 motr-* y u(/g6(kukk9o8y rcodhfion. At every point in its motion, the dirf/ r-ku uky9o6kogr( *dc8( hyection of the 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 suspended in the air at the end of (h6 )jheq7g1zy v+cqp7,ufjmfmv9w: a string held by a person. The pcwepu:yj,61 9(mf hj) 7hvmz7vq+f qgerson pulls on the string uniformly accelerating the block upward for a short time. During this time, which one of the following 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 is thef kh jt-w0ao wt0 gd .:yz;4d-or83cex net force constantly zero0t4jgofy0d8dxrta:c-; hzww -. ko 3e on the 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 grorz e .0w;cnx8a (:pzhw xqt aqx89a:f/und. A person intervenes and slows thw/ wafc e:: 0q aaznq;hx9p8z.x(8xtre 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 acceleration 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 khrt 91d hxavb52,id .ka-x(pequilibrium has three forces, F1 of 30 N, F2 of 50 N, and F3 of 70 N, acting tixvxd9rdhah k5 1b .k2 -,ap(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 rks f k:j-s/ w-b,c rnjf2f5cs:esultant with a magnitude of which of the followingf cwfk /c:f5-b:s sj,-krjs2n

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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 mostc wuf; k. di/6n0oz,as closely associated with Newton’s Third Law a 0i6skozn/f .;,c wudof 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 force does not cancel the action force47 + lt.mvt5jlzsvfx; 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 the floor of an elevator. The eleva165y kk9x emzs6c( jzrnqh)e 6tor is accelerating upward.1e mn6hx 6zreqk9ys5c j)(zk 6 Which one of the following choices best represents the Newton’s Third Law 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 constant speed. Whir ascn/hoaaie7xp 9x3s1x1 1 qxx1)s+ch one of the following choices cori peq1a+a1x/nx3s9 s)c 1o7xh1 xs rxarectly 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. Thebb43,q,t rrxlkc4i a1 batterswings and 314bb, k ,ctqar lri4xhits the ball. The magnitude of 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 on a table. On top of the book is a calculatzv n0m;+lhf d7or, also at rest. Which one of the following choices is the Newl;0 + mv7zdfnhton’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 Physics g s5vn5do.* w9-3)me u4,uflov ittquI class were in lab conducting an experiment related to Newton's Second Law. The coo 9gs-it 5dq ltue w,.nvouvf5mu*3)4llected data were displayed on the graph at the right. From this graph, what conclusions 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 2 oci5o;c n0gz/vsw7g on an object were doubled while at the same time the mass of the object was halved,then the acce0g52on; v go7/cczwsi leration 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 is 1 m(f1h3o:5e fc/gy)s-tzbg hm500 kg is accelerated uniformly from rest to a speed of 20 m/s in 10s. The magnitude of the net force accelerating thz h 5bs:- mgf)g/yh3tceo(f1me 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 is traveling down the road. The mass oft.u4ki08yaeq 9w:x oi the trailer is 4 times the mass of the tractor. If the tractor accelerates forwako0q xiywe498. ut:iard, 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 why l8 )sos)8q1j+ ypq8 zl4y kdq om4tk(dqarge tractor-trailer truc8smlqjktsyz o 8q8oy1))d+p 4qkqd4( ks generally accelerate much more slowly that automobiles?

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 frictionless rink throws a 2 o(,(bo5 lprr -vo2qgz kilogram ball, givingrv5rl g, q(oob 2z-(op 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 su5(y kr:s 3 .)xjsvwtgqrface of the earth with a weight of 100 newtons is acceleratv()stsgk3y 5 rqjx .w:ed 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 mass is 1200 kg is acceleh zt8h p4ol0.) q.fe7bf5 7 ap ,pn4npdjgy/qerated from rest by a constant force of 2400 N. What is the speed of 8)f0ogj/p7yahz 7 hpn. ,q4ep. blnef4qdp5tthe car 8.0 s after 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/r6elx;g 4va m9toci27 s slides across a rough horizontal floor before coming to rest. The frictional force acting on the block is 3.0 N. How far does the block slide before comingto7ecxi4 ml av96rg2; 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 velop mmoi dzqffz4v7a .4x()7:dxcity 4.0 m/s slides 8.0 m across a rough horizontal floor before coming td7.z(o4xfm:ip da7 qfv) mzx4 o 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 onl pt r33ocl7zf/( *hdk a horizontal 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 surface is*kcdor7 3 p/3zhltlf ( $\mu_k$ = 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 ms-yzm dw 85( 2szgyyq*/s accelerates uniformly to rest on a horizontal surface. The blockdzm s58-ws 2y(g yzy*q travels a distance of 12.0 m during the slide. Which one of the following choices best 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 sp w75j00sics0 o 4qkxglides across a patch of ice at a speed v with its brakes locked. It then hits075 icjssq0x04wp g ok dry pavement and skids to a stop in a distanced. The coefficient of kinetic friction between the tires and the dry road is μ .
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 ice at pityts+w 1wr.zs.ligk),4l6 ke0 u+l 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 ands.1+l i elpr.tu,w 04i6z)ls+wkgkyt 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 ankze5:a6reg/4 aye(e k emergency stop by slamming on the car's brakes and skidding to a stop. How fazy :ge4/ee5ker (ka6ar would the car have skidded if it had been traveling 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 au q x v/ktg4b ; 8)h.hoboxo;ov1fxgy.1tomobile must carefully control each of the following devices. Which of these devices can cause an acceleration in a moving car?;xo/ bkvo b.h. o1)8gq4tfvhyogx ; 1x
(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 240ylhn9 dt2i ds63hkq8/00 newtons. About how much time is needed to increase the rocket d9h2s3nl 86t /khy qdi’ speed from 12 m/s to 36 m/s near the surface 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 toz7(+j/q 5c: 0 lw( wvmnepdcec the right across a horizontal floor. A person called Ted exerts a force T to the right on the box. A person calle0v(:pccm e(cl5 /+w7jnqdz wed Mario exerts a force M to the left, which is half as large as the 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 rosn8 i8ijis2u8oc gus 3ql8 (crdf (hrpu+y929ller coaster tracks of equal length. Assume that on all tracks the roller coaster carts start from rest at the same elevation and moves frictionlessly over thes o2( 3l9c 9 s82hdsrui (fj88rp8n yiqi+gcuu 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 coas(v e 5rs75px3q*tecdhter tracks of equal length. Assume that on at3qe dep*(xrs7h vc55 ll tracks the roller coaster carts start from rest at the 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 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 cartro 4msg qrytxl7x 64tny.w dn832lls frictionlessly along the curved track from point A to point C under the influence of gravity. What would be the direction of the cart's acceleral 6t y3gyx2d478wx rq nst.n4mtion 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 across the floor by a rope which mfgi ;x c-2hm1s* mbo)gakes an angle of 300 with the horizontal. Which of the followin)fmg 1mi g;o -cbx2h*sg would be closest to the coefficient of kinetic friction between the box and the floor if a 250 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 as/ zx hai.t9k6t rest is pushed against a wall by a 100 N force as shown. Thecoefficient of kinetic friction is 0.30 while the coefficient of staticxtza9hi .6/ks 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 oc7g81kc * q5bfng/kg4a,e rz vf grass with a constant speed by applying a force P. The arrows in the diagram correctly indicate the dfrqv,b/n71e5 cgk g4 kzgc*a8 irections but not necessarily the magnitudes of the various forces on the lawn mower. Which of the following 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 tab/ z nu;4pnf(able. Neither is moving. Which of the following statements c; 4unpn(z/fba oncerning this situation is CORRECT?

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 remain v278*s8ynvpaoed /l is at rest on a sleigh as the sleigh is pulled up a hill with an increasing speed. The crate is not f8do2lyv a8e ivs p*7/nastened down to the sleigh. What 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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本习题练习题目来源于无忧得胜-网上国际课程 (https://5edu.win)，学生可刷题练习，扫右侧二维码或加微信skysky1258，获取更多资料
教师可以抽题组卷或一键复制本试卷，布置为在线考试或在线作业，全自动判分成绩一键排序导出，省时省力

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