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

标记此题

1#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.36: What happens to the inc h:q2f4veohm)l i+-zertia of an object when its velocity is doubled?

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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 dependjr)t1q1a wh (p on the quantity of matter present. Which of the following properties w(1tjpraq)h1 is NOT an intrinsic property?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

3#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

04.16: A 20 kg boulder rest ).tm5 izj0wqn6l/4yh7mg l bvs on the surface of the Earth. Assume the Earth has ma iv y6zt4n/.l lm5mjg hbw)q70ss $5.98 \times 10^{24} \; kg$ and $g = 10\;m/s^{2}$ . What is the magnitude of the gravitational force that the boulder exerts on the Earth?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

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 faj6khstrct +( :ll near the surface of the Earth. What is the magnitude of the gravitational force acting on the earth by the sphere? The r+ktct: (sjh 6Earth mass is $5.98 \times 10^{24} \; kg$ .

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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’w9(pi aub9v7z 3w+ts6lq 1z:+bwxsoys velocity to increase while its acceleration decreasb:zzsov6 w wub9(wias+l97+yp3x q1 tes?

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 mopq tg2yci8+95c kitjph12 6qrtion, the direction of the particle’s momentumqic2 p+6j 2qykt81cthg9 i p5r 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 a strxqukdh .jim+w 33+tc 3ing held by a person. The person pulls on the string uniformly accel+ucqd33+x t3jhm.kwi erating 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 i*3 c(wtbpl .88 i,t ppu+lgtscs the net force constantly zero on the ,tt8gps wt*bl lp.p8ciuc+(3object?

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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

9#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

13.28: An object is in free fallkia/8evt ,y r0rs.nl: close to the ground. 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 acceleration from gravity is t/ erv y,ikn0.s :ral8g.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 50 N, u9ws+f;ew /6lix ekf:and F3 of 70 N, acting on it. The magnitude of the resul9 k+6fs ix/:lwe;ewfutant ofF1 and F2 is

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

11#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

01.07: A force of 6 Newtons an2vw+bg 78bx+m0 ht tbdd a force of 10 newtons can be combine to form a reswmtb0 hxg8b27bdtv + +ultant with a magnitude of which of the following

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

12#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

10.06: Which of the following statemt u:p4s 8xhqv6oc ;zptv9 c;/qents is most closely associated with Newton’scv4 ;c8 uqto6x:hz/t;9p q spv Third Law of 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.”

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

13#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

95.06: The reaction )kgs ,.mal6gi force 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

14#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

14.14: A box rests on the pb6 yr1e0ji4 bfloor of an elevator. The elevator is accelerating upward. Which one of the i1erp60 jb4yb 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

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 conj+s-1zgn; jk wstant speed. Which one of the following choices correctly describes the Newton’s Third Law pair force to the air resistance acting on the skydiver du-njkzw+jg 1s;ring 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

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/xas9k cru 0s8pnq; 8w.s. The batterswings and hits the ball. The magnitude of the force thaskp r0;8n9a.sc q 8uwxt 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 fhz:c f. aft w2o2 at7.83fy:qgj6galon a table. On top of the book is a calculator, alsoz:wt cojaf6hlt2faa.:8 gf3. 7gyq f2 at rest. Which one of the following choices 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

18#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

05.06: The students in a Physics I class were in lab conducting an exper6iac8v cr3 j*wy7g eio;u.my8 iment related to Newton's Second La w8iyg*rcv7u.3ema8oiycj; 6 w. The collected 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

19#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

99.03: If the net force xl ba6.cfih45s(pa -0rsoy do: ug7r7 on an object were doubled while at the same time the mass of the object was halvedus: o7aih7( f 6y lr5px0d.sgc4ao -br,then the acceleration of the object is

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

20#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

96.15: A car whose mass is 1500 kg w0 0 3i d4s8kdhk) b4l/ -ecuiqux;uueis accelerated uniformly from rest to a speed of 20 m/s in s ;h 0/8c4qkiuedux-0uiluwd )b4e 3k10s. The magnitude of the net force accelerating the car is:

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 rk (8w8ws1gjm 6xv. zmsoad. The mass of the trailer is 4 times the mass of the tractor. If the tw1z sm 8kg8js6( v.xwmractor 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 large tractor-23265q sri atccbz-wj5g)gtotrailer trucks gec -2s2tga655cbg o3tjz qr)iw nerally 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 frictzfp *4wsb uz2yjd5ih74n qb.6ri0 5 zrionless rink throws a 2 kilogram ball, giving the ball a velocity of 10.0 m/s. Which statejzbr nhb2 wi6p4.yizrfdz s75*q 50u4 ment 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 of 100 newtons isnxnmq ,/t7v) o4pu)vv acceleratedv4)7)ut xn qvm/pv,on at $4\;m/s^{2}$ . What is the net force on the object?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

25#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

98.25: A car whose mass isg)) 8 m43ova3kqh-qzooq fk;f 1200 kg is accelerated from rest by a constant force of 2400 N. What is the speed offqkh33omk -8ov 4) zoq;a )gqf the car 8.0 s after beginning?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

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 initialro /w+ *+,qmx- av1.tklsw qbx speed 4.0 m/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 slid wvxq,/1wr+.b a+otlxq *ksm- e before coming to rest?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

27#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

95.38: A block with initial .wz y4v/o pe(4. gig( heq97dph82yx)gfkj svvelocity 4.0 m/s slides 8.0 m across a rough horizontal floor before coming to rest. The coefficient ofdgqe2(p(epgy jwzg4 hk vv.ifo9/ ).s h8y4x7 friction is:

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

28#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

09.21: A 20.0 kg box rema6kn p+e80mcvk:jns p 7t)y9iqins at rest on a horizontal surface while a person pushes directly to the right on the box with a force of 60N.ic:9+kp jvetk s n60p)q7yn 8m The coefficient of kinetic friction between the box and the surface 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?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

29#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

13.16: A block initiabb94 c lr+5wkzlly moving at 8 m/s accelerates 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 best represents the coefficient of kinetic friction between the surface and the block?l+r4w b5czbk9

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

30#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.21: A car of mass m slides across an4im6 bm ct75t patch of ice at a speed v with its brakes locked. It then hits dry pavement and skids to a stop in a dism nm75tb4itc6tanced. 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

31#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.22: A car of mass m slides10a5 wgvpin;3m2yp xh across a patch of ice at a speed v with its brakes locked. It then hits dry pavement and skidsm12nvpg3xi0wpa ;h5 y 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 speed of 2v, it would have skidded a distance of

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 slamming on the car'w ,a4pk:e ai8 oldixrq8+))hd s brakes and skidding to a stop. How far would the car have skidded if it had been traveling twice as faswhdl+:8karqio ea8 p4xd))i,t?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 ea-xp3g 0)- eklrf/h b:hqkahl. ch of the following devices. Which of these devices can cause an acceleration in a moving car-kkf h)qa-e.l /:lg0x3hbh r p?
(1) the break pedal ( 2) the gas pedal ( 3) the steering wheel

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

34#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

00.25: The net force on a rockeit)*n ,wizf+50ewf hu t with a weight of 15000 newtons is 24000 newtons. About how much time is needed to in5)nwe f* i w,ufzh0ti+crease the rocket ’ speed from 12 m/s to 36 m/s near the surface of the Earth at takeoff?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

35#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

07.21: A box slides to the p9ctewytn bopq;r zk6h(+68kbs; wn lm-6 g; +right across a horizontal floor. 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 force T. Given that there is friction f and the box accelerates to the righttnk+ n gl e b;w6(psoy b;h;-m+z8p6w9rk qt6c, rank the sizes of these three forces exerted on the box.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 track0l(gf- 0iq1vjk:f)zae.il . sto8x fes of equal length. Assume that on all tracks the roller coaster carts start from rest at the same elevj(vifql t :lx- kaf0)ie1s. o0 f8zg.eation 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

37#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

02.28: The diagram below shows three rni88njc,ng 3mdd6h8ne8i ikm21*m4k.tt l rt oller coaster tracks of equal length. Assume that on all tracks the roller coaster carts start from rest at the same elevation and movk6mr8. tntd1e43icn2ii , mn8nj 8ht8 * dmkgles 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?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

38#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

02.29: Assume the rollercoaster cartrolv)f;jc*ycj+ v3y.ea sl2*gytls frictionlessly along the curved track from point A to point C under the influence of gravity. What would be the direction of the cart'sts3.;)f j+* acylcv y2gv*y ej acceleration at point

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 dij0 xpw,*pa,)rwf s: oragged across 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 newton force on the rope is required to move the crate atppisf0*,:,x aj)row w a constant speed of 20 m/s as shown in the diagram?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 i17hmm2gdaq0i6 q o-jns pushed against a wall by a 100 N force as shown. Thecoefficient of kinetic friction is 0.30 while the coefficient of static friction is 0.50. What is true of the friction actingm j7 a1q6od 02mgih-nq 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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 qrue b,9b go81rgih rxe2)2 /whorizontal patch of grass with a constant speed by applying a forc o8g2 urbe)2x9iqbe1gr, wr /he 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 following relations among the various force magnitudes, W, f, N, P is CORRECT?

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

标记此题

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. Neither is m3c 04ir;f bn3px5zb qboving. Which of the following stb4ni z ;0b5rb xfc3q3patements concerning 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.

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

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

标记此题

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 ong *w;pvj8u h6j a sleigh as the sleigh is pulled up a hill with an increasing speed. The crate is not fastened down to the sle;*upjj vw6 8hgigh. 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

绑定到本题的附件链接:
绑定到本题的上传图片:

参考答案:

进入本题讨论区，参与讨论

账号		自动登录	找回密码
密码			立即注册

网页聊天 (离线可收发)

加微信咨询 (申请一对一课程辅导，加本站学习交流群）

电话咨询：

联系管理员：

查看帮助：

未使用图片

本次作答已使用

1	2	3	4	5	6	7	8	9	10
11	12	13	14	15	16	17	18	19	20
21	22	23	24	25	26	27	28	29	30
31	32	33	34	35	36	37	38	39	40
41	42	43

1	2	3	4	5	6	7	8	9	10
11	12	13	14	15	16	17	18	19	20
21	22	23	24	25	26	27	28	29	30
31	32	33	34	35	36	37	38	39	40
41	42	43

1	2	3	4	5	6	7	8	9	10
11	12	13	14	15	16	17	18	19	20
21	22	23	24	25	26	27	28	29	30
31	32	33	34	35	36	37	38	39	40
41	42	43