Physics Unit6: Work and Energy - 题库网 (tiku.one)

1#

What is the correct unit of work expg2w 26h ruf :0epjn0jpressed in SI units?

A. $kg m/s^2$

B. $kg m^{2}/s$

C. $kg m^{2}/s^2$

D. $kg^2 m/s^2$

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

Can work be done on a system if a;hvf)ov oi 8 9d1wv(xthere is no motion?

A. Yes, if an outside force is provided.

B. Yes, since motion is only relative.

C. No, since a system which is not moving has no energy.

D. No, because of the way work is defined.

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

If you push twice as hard against a stationary bri.qw gv+b xlq-) a7q7vdck wall, the amount of work you doql-. vqqdag) xw 7vb7+

A. doubles.

B. is cut in half.

C. remains constant but non-zero.

D. remains constant at zero.

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

4#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 50-N object was lifted 2.0 m vertically and is being held there. H*/1xm2eu/3sagfwxlba( e xl 7ow much work ise31/x/*alauswx (b g lef7x m2 being done in holding the box in this position?

A. more than 100 J

B. 100 J

C. less than 100 J, but more than 0 J

D. 0 J

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

If you walk 5.0 m horj:lne yse43r/fuikdc b -yy .8p,m:2gizontally forward at a constant velocity carrying a 10-N object, the amount of fbnu8 c2:yd3kjs y4e ig p/-.ye,lrm:work you do is

A. more than 50 J.

B. equal to 50 J.

C. less than 50 J, but more than 0 J.

D. zero.

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

6#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A container of water is lifted vertically 3.0 m th cjak;hp1q j cy,fd+:c js5,dw 2ls57wen returned to its original position. If the total p2q5+ak7cj,jcwsfyd wd : c1,lh j; 5sweight is 30 N, how much work was done?

A. $45 \; J$

B. $90 \; J$

C. $180 \; J$

D. No work was done.

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

Does the centripetal force acting on an object do work on the ob:d7y8pn57rl (xkn lhj ject?

A. Yes, since a force acts and the object moves, and work is force times distance.

B. Yes, since it takes energy to turn an object.

C. No, because the object has constant speed.

D. No, because the force and the displacement of the object are perpendicular.

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

You throw a ball straight up. Compa,-qx *q r+jpqere the sign of the work done by gravity while the ball goes up w r qxe-,qj*q+pith the sign of the work done by gravity while it goes down.

A. Work is + on the way up and + on the way down.

B. Work is + on the way up and - on the way down.

C. Work is - on the way up and + on the way down.

D. Work is - on the way up and - on the way down.

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

The area under the cjfa/.a n: kygbt./i)g urve, on a Force versus position (F vs. x) graph, representsafty./b.)gjk n/g:ia

A. work.

B. kinetic energy.

C. power.

D. potential energy.

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

10#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

On a plot of Force versus + 4hmez)ci)nu position (F vs. x), what represents the work done by the f+mu4nc)iezh) orce F?

A. the slope of the curve

B. the length of the curve

C. the area under the curve

D. the product of the maximum force times the maximum x

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

11#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The quantity $\frac{1}{2} \; mv^2$ is

A. the kinetic energy of the object.

B. the potential energy of the object.

C. the work done on the object by the force.

D. the power supplied to the object by the force.

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

If the net work done5**mllb jt+gxd0,j xl on an object is positive, then the object's kinetic energy

A. decreases.

B. remains the same.

C. increases.

D. is zero.

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

If the net work done on an object is negative, then the obj;6a55elh qgp vect's kinetic energy

A. decreases.

B. remains the same.

C. increases.

D. is zero.

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

14#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If the net work done on an object is zero, then the object's kinetz(c,vi ge4)v 4yasiv8ic energy

A. decreases.

B. remains the same.

C. increases.

D. is zero.

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

15#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A truck weighs twice as mu70tw pxg- pt .k7vd,asch as a car, and is moving at twice the speed of the car. Which statement is true about the truck's kinetic energy comp7.k d p07w,gv pax-sttared to that of the car?

A. All that can be said is that the truck has more kinetic energy.

B. The truck has twice the kinetic energy of the car.

C. The truck has 4 times the kinetic energy of the car.

D. The truck has 8 times the kinetic energy of the car.

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

Car J moves twice as fast as car K, and car J has half the mass of ca8vl (- t7cpuucr K. The kinetic energy of caru8pvc-uc( lt7 J, compared to car K is

A. the same.

B. 2 to 1.

C. 4 to 1.

D. 1 to 2.

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

An object hits a wall and bounces back with h:* hwrv-66foz vww2bw alf of its original speed. What is the ratio of the final kinetic energy to the initial w:vof2 w6hrb6w wv* z-kinetic energy?

A. \frac{1}{2} \;

B. 1/4

C. 2

D. 4

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

A brick is moving at a speed of 3 m/s and a pebble is moving at a x(s ws3cl08dqc0x/+wbwn:gq speed of 5 m/s. If both objects have the same kinetic energy, what bs qcxns/w :x(8lg +dwwc30 0qis the ratio of the brick's mass to the rock's mass?

A. 25 to 9

B. 5 to 3

C. 12.5 to 4.5

D. 3 to 5

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

19#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 4.0-kg mass is moving witjiv hlrka935 g ivi271h speed 2.0 m/s. A 1.0-kg mass is moving with speed 4.0ivhk7v lr321g9jiia 5 m/s. Both objects encounter the same constant braking force, and are brought to rest. Which object travels the greater distance before stopping?

A. the 4.0-kg mass

B. the 1.0-kg mass

C. Both travel the same distance.

D. cannot be determined from the information given

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

You slam on the brakes of your car in k6hv4nihgewy mjesq:s+-jy11 b52 2x a panic, and skid a certain distance on a straight, level road. If you had been traveling twice as fast, what distance would the car have skidded, under the same con2js+ e6 y:gn1svw qhb12hxymej 5-ki4ditions?

A. It would have skidded 4 times farther.

B. It would have skidded twice as far.

C. It would have skidded 1.4 times farther.

D. It is impossible to tell from the information given.

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

A planet of constant mass orbits the Sun i79ek9b:om es dn an elliptical orbit. Neglecting any friction effects, we9s 7eb:dom9 khat happens to the planet's kinetic energy?

A. It remains constant.

B. It increases continually.

C. It decreases continually.

D. It increases when the planet approaches the Sun, and decreases when it moves farther away.

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#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State the work-energy princ:z8o qbieo9.p 4wcmj ;iple.

该题自我估分: (必填) (满分:1.0分)

绑定到本题的附件链接:
绑定到本题的上传图片: (问答题类型题目图片/附件必须插入上方文本框，否则会被移除题目绑定)

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

The quantity mgy is

A. the kinetic energy of the object.

B. the gravitational potential energy of the object.

C. the work done on the object by the force.

D. the power supplied to the object by the force.

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

The quantity $\frac{1}{2} \; kx^2$ is

A. the kinetic energy of the object.

B. the elastic potential energy of the object.

C. the work done on the object by the force.

D. the power supplied to the object by the force.

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

Is it possible for a system j*c(y ujiz9e(dsgc8 8to have negative potential energy?

A. Yes, as long as the total energy is positive.

B. Yes, since the choice of the zero of potential energy is arbitrary.

C. No, because the kinetic energy of a system must equal its potential energy.

D. No, because this would have no physical meaning.

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

26#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is released fromwx ttx4uhg3*.- sz*cy rest a height h above the ground. A second object with four times the mass of the first if released from the same height. The potential en4-g* *x.y3xtzuswc thergy of the second object compared to the first is

A. one-fourth as much.

B. one-half as much.

C. twice as much.

D. four times as much.

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

A 0.200-kg mass attached to the eu 7h8-ozhg vw0nd of a spring causes it to stretch 5.0 cm. If another 0.200-kg mass is added to the spring, the potential energy of the spring will h8z7-u0 whgov be

A. the same.

B. twice as much.

C. 3 times as much.

D. 4 times as much.

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

28#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The total mechanical energy of5wbj/jav -j0fq* ev/f et*3lf a system

A. is equally divided between kinetic energy and potential energy.

B. is either all kinetic energy or all potential energy, at any one instant.

C. can never be negative.

D. is constant, only if conservative forces act.

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

An acorn falls from a tree. Comss dy atapk. i/w8;r(nr4lc31 pare its kinetic energy K, to its potential energy 8a;atr/ c(s sd1npikr4y.w3l U.

A. K increases and U decreases.

B. K decreases and U decreases.

C. K increases and U increases.

D. K decreases and U increases.

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

Describe the energy of a car driving up a*0dy d 2ij n x-e4mkx0jlu4t4h hill.

A. entirely kinetic

B. entirely potential

C. both kinetic and potential

D. gravitational

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

A lightweight object and a very heavy object are sliding with equal speeds al4st0g j dlku0)*:rmo wk c3h1wong a level frictionless surfacekswkl * r 0j3d0wt:hu4) cgo1m. They both slide up the same frictionless hill. Which rises to a greater height?

A. The heavy object, because it has greater kinetic energy.

B. The lightweight object, because it weighs less.

C. They both slide to the same height.

D. cannot be determined from the information given

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

Consider two masses f4ov7;hh - l;:dncic5ccdxr .$m_{1}$ and $m_{2}$ at the top of two frictionless inclined planes. Both masses start from rest at the same height. However, the plane on which $m_{1}$ sits is at an angle of $30^{\circ}$ with the horizontal, while the plane on which $m_{2}$ sits is at $60^{\circ}$. If the masses are released, which is going faster at the bottom of its plane?

A. $m_{1}$

B. $m_{2}$

C. They both are going the same speed.

D. cannot be determined without knowing the masses

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#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State the principle of conservation of mechanical energy for cw9-iqop(ep ftp ch ,m/r1)3lzonservative forces.oqppfhztelr) 1 mw /c9p(-,i 3

该题自我估分: (必填) (满分:1.0分)

绑定到本题的附件链接:
绑定到本题的上传图片: (问答题类型题目图片/附件必须插入上方文本框，否则会被移除题目绑定)

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

A ball falls from the top owf 4s 3+w9qcujf a building, through the air (air friction is present), to the ground below. How does the kinetic energy (K) just before striking the ground compare to the potential energy (U) at the top of th4 jfqcw 9sw+u3e building?

A. K is equal to U.

B. K is greater than U.

C. K is less than U.

D. It is impossible to tell.

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

A ball drops some distance and gains 30 J of kinetic2dzf -0bbok41mcw6+fz *bj ex energy. Do not ignore air resistance.edb0*ffb-6o1kc4b+zx mz w 2j How much gravitational potential energy did the ball lose?

A. more than 30 J

B. exactly 30 J

C. less than 30 J

D. cannot be determined from the information given

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

A ball drops some distance and loses 30 J of gravin .q 5.wtnn0h cy7w lbi5w;l(stational potential energy. Do not ignore air re;lnq5.w (n wyl b0wc57i.tnsh sistance. How much kinetic energy did the ball gain?

A. more than 30 J

B. exactly 30 J

C. less than 30 J

D. cannot be determined from the information given

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#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State the law of conservation of enerwk5i2,tcf8b- kwxos :gy.

该题自我估分: (必填) (满分:1.0分)

绑定到本题的附件链接:
绑定到本题的上传图片: (问答题类型题目图片/附件必须插入上方文本框，否则会被移除题目绑定)

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

The quantity Fd/t ise)e 90er+ kdompxq dfl eb l-8+35or:f

A. the kinetic energy of the object.

B. the potential energy of the object.

C. the work done on the object by the force.

D. the power supplied to the object by the force.

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

What is the correct unit of power ex7j;m6xt7ca .,m wyfng iv6ki(pressed in SI units?

A. $kg m/s^2$

B. $kg m^{2}/s^2$

C. $kg m^{2}/s^3$

D. $kg^2 m/s^2$

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

40#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Of the following, which is not a unit of powep(m;p hgm4e/8 c;;r+nbrf*epy p:ck8w u:upq r?

A. watt/second

B. newton-meter/second

C. joule/second

D. watt

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

Compared to yesterday, you did 3 times the work in one-third the time. To do sp z) e6p(+e ;*tjjqhwvo, your powv6jp*ej+ pwt)(;z hqeer output must have been

A. the same as yesterday's power output.

B. one-third of yesterday's power output.

C. 3 times yesterday's power output.

D. 9 times yesterday's power output.

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

To accelerate your car aifw37tc bm ,gay0/z5 vt a constant acceleration, the car's engine must

A. maintain a constant power output.

B. develop ever-decreasing power.

C. develop ever-increasing power.

D. maintain a constant turning speed.

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

43#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object is lifted .lgqd unqstlv wug 9r.: 0l)71vertically 2.0 m and held there. If the object weighs 90 N, how much work was dor9:wg70gll usn 1.vu .)tldq qne in lifting it?

A. $360 \; J$

B. $180 \; J$

C. $90 \; J$

D. $0 \; J$

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

44#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

You lift a 10-N physics book up in the ai2q ss.oxano,0r a distance of 1.0 m, at a constant velocity of 0.50 m/s. What is the work done by the weight a0 qxno2,s.osof the book?

A. +10 J

B. -10 J

C. +5.0 J

D. -5.0 J

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

45#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 500-kg elevator is pulled upq-kt/,je 4 . ohdroy*jward with a constant force of 5500 N for a distance of 50.0 m. What is the work done t/h4j- r.djqyeo,o*k by the 5500 N force?

A. $2.75 \times 10^{5} \; J$

B. $-2.45 \times 10^{5} \; J$

C. $3.00 \times 10^{4} \; J$

D. $-5.20 \times 10^{5} \; J$

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

46#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 500-kg elevator is pulled upward with a constant force of 5500 N fo.iz(rtx wj,7ir a distance of 50.0 m. What is the work doi zrtj.7w( xi,ne by the weight of the elevator?

A. $2.75 \times 10^{5} \; J$

B. $-2.45 \times 10^{5} \; J$

C. $3.00 \times 10^{4} \; J$

D. $-5.20 \times 10^{5} \; J$

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

47#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 500-kg elevator is pulled upward with a constant force of 5500 N for a disi b9 f8yyc/6tka,/rb vtance of tc 9/bv/ k 6f,yiyarb850.0 m. What is the net work done on the elevator?

A. $2.75 \times 10^{5} \; J$

B. $-2.45 \times 10^{5} \; J$

C. $3.00 \times 10^{4} \; J$

D. $-5.20 \times 10^{5} \; J$

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

48#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 30-N box is pulled 6.0 mm faxi+4np2wk4 8e6 gk up along a $37^{\circ}$ inclined plane. What is the work done by the weight (gravitational force) of the box?

A. $-11 \; J$

B. $-1.1 \times 10^{2} \; J$

C. $-1.4 \times 10^{2} \; J$

D. $-1.8 \times 10^{2} \; J$

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

49#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 4.00-kg box of fruit slides 8.0 m down a rr6 l5 zjzv:vglz(m/p 4amp, inclined at $30^{\circ}$ from the horizontal. If the box slides at a constant velocity of 5.00 m/s, what is the work done by the weight of the box?

A. $157 \; J$

B. $-157 \; J + 78.4 \; J$

C. $78.4 \; J$

D. $-78.4 \; J$

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

50#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Matthew pulls his little sister Sarah in a sled on an icy surfacefpqe:ygl0rras. +0qa2e3 m w4t0i7xx (assume no friction), with atp rqrfl74 .2:ge0qx+imsa x 0a3ew0y force of 60.0 N at an angle of $37^{\circ}$ upward from the horizontal. If he pulls her a distance of 12.0 m, what is the work done by Matthew?

A. $185 \; J$

B. $433 \; J$

C. $575 \; J$

D. $720 \; J$

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

51#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A force moves an object in the direction of the forcnhmyx xfho312 k:l9w0e. The graph in Fig. 6-1 shows the force versy2hn h1fk:m0x wxl93o us the object's position. Find the work done when the object moves from 0 to 2.0 m.

本题所包含的其它图片:

A. $20 \; J$

B. $40 \; J$

C. $60 \; J$

D. $80 \; J$

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

52#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A force moves an object in the direction 3i9 :hqqw+tu 4 i4oamtof the force. The graph in Fig. 6-1 shows the force versus the object's position. Find the work done when the objeqt:it+ aw49ui mq3h o4ct moves from 2.0 to 4.0 m.

本题所包含的其它图片:

A. $20 \; J$

B. $40 \; J$

C. $60 \; J$

D. $80 \; J$

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

53#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A force moves an object in the direction o 6jbe9fjp-dqektr: /b)4aq8ff the force. The graph in Fig. 6-1 shows the force versus the object's fjef j p kqrq)tb4-e6a9db8:/position. Find the work done when the object moves from 4.0 to 6.0 m.

本题所包含的其它图片:

A. $20 \; J$

B. $40 \; J$

C. $60 \; J$

D. $80 \; J$

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

54#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A force moves an object in the direction of the force. The graph in Fig. 6-1 sh94uj e t9ihu,z fc7*teows the force versus the object's position. Find the work doui9zt4 jet 97e*uf h,cne when the object moves from 0 to 6.0 m.

本题所包含的其它图片:

A. $20 \; J$

B. $40 \; J$

C. $60 \; J$

D. $80 \; J$

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

55#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A horizontal force of 200 N is applied to move a 55-kg cart (initiafq4 skc, g:2tully at rest) across a 10 m level surface. What is the final kinetic energy of the cagst,f4kc2 u q:rt?

A. $1.0 \times 10^{3} \; J$

B. $2.0 \times 10^{3} \; J$

C. $2.7 \times 10^{3} \; J$

D. $4.0 \times 10^{3} \; J$

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

56#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A horizontal force of 200 N is applied to o*jv;yma8d 2+elv4bc move a 55-kg cart (initially at rest) across a 10 m level surface. 8lmo ;day4vveb2c* j + What is the final speed of the cart?

A. 73 m/s

B. 36 m/s

C. 8.5 m/s

D. 6.0 m/s

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

57#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 10-kg mass is moving with a speed of 5.0 m/s. Howp 5c;nx )me3cvk5bd/j much work is required to stop thxjb5dp/5 k3c; )c enmve mass?

A. $50 \; J$

B. $75 \; J$

C. $100 \; J$

D. $125 \; J$

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

58#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

If it takes 50 m to stop a car initially moving at 25 m/s, what disobxgz55lc.e p *5y lq5tance is required to stop a car moving at 50 m/s under the same conditqx5y*b5o5 e l. gpcl5zion?

A. $50 \; m$

B. $100 \; m$

C. $200 \; m$

D. $400 \; m$

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

59#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A spring-driven dart gun propels a 10-g dart. It //vs p7* ixf9;kbxaqdr z)qu8 is cocked by exerting a force of 20dx7r xq)ka9z;b/u8/pv sq *fi N over a distance of 5.0 cm. With what speed will the dart leave the gun, assuming the spring has negligible mass?

A. 10 m/s

B. 14 m/s

C. 17 m/s

D. 20 m/s

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

60#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 100-N force has a horizontal component of 80 N and a vertical component of mzfa(s h7 v-1*:stjn h)hf x2r60 N. The force is applied to a box which rests on a level frictionless floor. The cart starts from rest, anf2*atvhmjzfx(n1s - :)h srh 7d moves 2.0 m horizontally along the floor. What is the cart's final kinetic energy?

A. $200 \; J$

B. $160 \; J$

C. $120 \; J$

D. zero

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

61#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An arrow of mass 20 g is shot horizontally into a bale of hay, striking the k3*(p ae jyo)uhay with a velocity of 60 m/s. It pe(oju*e ay)p3 knetrates a depth of 20 cm before stopping. What is the average stopping force acting on the arrow?

A. $45 \; N$

B. $90 \; N$

C. $180 \; N$

D. $360 \; N$

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

标记此题

62#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 15.0-kg object is moved f tapk+o m2l2u hav:.k;rom a height of 7.00 m above a floor to a height of 13.0 m above the flo.2mv2ktu; olpa+hk:aor. What is the change in gravitational potential energy?

A. zero

B. 1030 J

C. 1176 J

D. 1910 J

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

63#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 400-N box is pushed up an inclined plane. The plane is 4.0 m lohc* f21)b(,mh4a;gf ) m qqknjqrw3cfng and rises 2.0 m. If the plane is frictionless, how much work was done * fg mc124hqahr3 wf)()m jf,nkcqqb ;by the push?

A. $1600 \; J$

B. $800 \; J$

C. $400 \; J$

D. $100 \; J$

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

64#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 10-kg mass, hung onto a spring, causes the spring to stretch 2.0 cm. What iub *oc omu2z*m-0n- afs the spring conscmuzo bmo* fnu-a-*02tant?

A. $4.9 \times 10^{3} \; N/m$

B. $5.0 \times 10^{3} \; N/m$

C. 20 N/m

D. 2.0 N/m

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

65#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A spring is characterized by a spring constant of 60 N/m. How m*h qn nsdlpkyz64u938q3kn i7uch potential energy does it store, when stretched by 1ik339 kpzyq* ds l4nu87qh6 nn.0 cm?

A. $3.0 \times 10^{-3} \; J$

B. $0.30 \; J$

C. $60 \; J$

D. $600 \; J$

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

66#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Calculate the work required to compress an initially uncompressed sprinqyn- 0 0+cdvyvd e,nxx.9rlc.eo+.ae g with a spring constad+ r.-ve..cq cov9,y l+ x ex0aden0ynnt of 25 N/m by 10 cm.

A. $0.10 \; J$

B. $0.13 \; J$

C. $0.17 \; J$

D. $0.25 \; J$

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

67#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

What work is required to stretch a sclpj5sc9n 5dy6*r x ,t*9ekjq pring of spring constant 40 N/m from x = 0.20 m to 0.2 9j*kcejqnydx5 ,s95trl c6*p5 m? (Assume the unstretched position is at x = 0.)

A. $0.45 \; J$

B. $0.80 \; J$

C. $1.3 \; J$

D. $0.050 \; J$

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

68#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A spring with a spring constant of 15 N/m is initially ct(2svu sx. r g1o+fwn(ompressed by 3.0 cm. How much work is required to compress thto.x n(u (sgsr1 wf2+ve spring an additional 4.0 cm?

A. $0.0068 \; J$

B. $0.012 \; J$

C. $0.024 \; J$

D. $0.030 \; J$

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

69#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 60-kg skier starts from rest q-n zc(g9 f3kkk5r,t( h kpyt3from the top of a 50-m high slope. What is the speed of the slier on reaching the bottom of the slope? (Neglect frfc-(ytqhpk3g (kkr,5zn 3t9kiction.)

A. 22 m/s

B. 31 m/s

C. 9.8 m/s

D. 41 m/s

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

70#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A skier, of mass 40 kg, pushes off the top of a hill with an initi*lg5 f r0k 1z6zlz+uiual speed of 4.0 m/s. Neglectin f 6zkgu05u zr*+z1lilg friction, how fast will she be moving after dropping 10 m in elevation?

A. 7.3 m/s

B. 15 m/s

C. 49 m/s

D. 196 m/s

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

71#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An object slides down a frictionless inclikx4 n3 d)gkfyy+ .jrj(ned plane. At the bottom, it has a speed of 9.80 m/s. What is the vertical heixy.)nyfgdkj (j+r 3k4 ght of the plane?

A. $19.6 \; m$

B. $9.80 \; m$

C. $4.90 \; m$

D. $2.45 \; m$

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

72#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1.0-kg ball falls to the floor. When it is 0.70 m above the floor, its gj/g 2t. un+; mnoj-57jgiq enpotential energy exactly equals its kinetic energy. How faj/; i5nogn- .2ugqgmn+ jj te7st is it moving?

A. 3.7 m/s

B. 6.9 m/s

C. 14 m/s

D. 45 m/s

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

73#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A toy rocket, weighing 10 N, blasts l is1t:22 cmfystraight up from ground level with a kinetic energy2 mfitlc:2 1sy of 40 J. At the exact top of its trajectory, its total mechanical energy is 140 J. To what vertical height does it rise?

A. $1.0 \; m$

B. $10 \; m$

C. $14 \; m$

D. $24 \; m$

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

74#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A projectile of mass m leaves the ground with a kinetic xyo3i os x,b6-v:kby8energy of 220 J. At the highest point in its trajectory, its kinetic energy is 120 J. To what vertical height, relative to its launch poi68os:-obyy bxv xk,i3nt, did it rise?

A. $\frac{220}{mg} \; m$

B. $\frac{120}{mg} \; m$

C. $\frac{100}{mg} \; m$

D. Impossible to determine without knowing the angle of launch

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

75#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A roller coaster starts from rest at a poin 9wr 55c6udyuiyjo)+w5s 0ev st 45 m above the bottom of a dip (See Fig. 6-2). Neglect friction, what will be the speed of the roller coaster at the top of the nej90w scy) udiurw e5o6y5v+5sxt slope, which is 30 m above the bottom of the dip?

本题所包含的其它图片:

A. 14 m/s

B. 17 m/s

C. 24 m/s

D. 30 m/s

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

76#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A roller coaster starts with a speed of 5.0 m/s a0 s yzqkte*/v3t a point 45 m above the bottom 0keyt/qv 3*sz of a dip (See Fig. 6-2). Neglect friction, what will be the speed of the roller coaster at the top of the next slope, which is 30 m above the bottom of the dip?

本题所包含的其它图片:

A. 12 m/s

B. 14 m/s

C. 16 m/s

D. 18 m/s

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

77#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A roller coaster starts at a point 30 m above the bottom of a dip witp)s :.u1( ngv,.ee gxsnpnv(cg 6ejh5h a speed of 25 m/s (See Fig. 6-2). Neglect friction, what will be the speed ofc x.sh1()snugv(penn e, ep.g5gvj 6: the roller coaster at the top of the next slope, which is 45 m above the bottom of the dip?

本题所包含的其它图片:

A. 14 m/s

B. 16 m/s

C. 18 m/s

D. 20 m/s

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

78#

( 1.0 分) 切至整卷模式搜藏此题

What is the minimum speed of the ball at the bottom 9jn ;l02 p 8m.rb.+rvvsy hd x./uxlnjof its swing (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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

79#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A:2.2 m/s

A. 3.1 m/s

B. 4.4 m/s

C. 4.9 m/s

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

80#

( 1.0 分) 切至整卷模式搜藏此题

难度:2

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

81#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A pendulum of length 50 cm is pulled 30 cm away from the verticur5ei;wh8 jxjt 3,d gw2 dz, 0ea4lbt:zyb/.bal axis and released f ,be0 wdid :4guza tyb2r8t,j. 3/ejzlxb5h;w rom rest. What will be its speed at the bottom of its swing?

A. 0.50 m/s

B. 0.79 m/s

C. 1.2 m/s

D. 1.4 m/s

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

82#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1500-kg car moving at 25 m/s hits an initially uncompressed horizontal-smi-d1) cbmuyp6 gfbzc.z 9- spring wig-yfsu6--mcd1i .b9 pz )czmbth spring constant of $2.0 \times 10^6 \; N/m$. What is the maximum compression of the spring? (Neglect the mass of the spring.)

A. $0.17 \; m$

B. $0.34 \; m$

C. $0.51 \; m$

D. $0.68 \; m$

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

83#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A driver, traveling at 22 m/s, slows down her 2000 kg car to stop fopzz -07rs, kdfr a red light. What work is done by the friction force arf,7p dk0sz-zgainst the wheels?

A. $-2.2 \times 10^{4} \; J$

B. $-4.4 \times 10^{4} \; J$

C. $-4.84 \times 10^{5} \; J$

D. $-9.68 \times 10^{5} \; J$

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

84#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The kinetic friction force between a 60.0-kg 1szwmmk05 p;jd2 vrly;xr :k (object and a horizontal surface is 50.0 N. If the initial speed of the object is 25.0 m/s, wha;vszdkjr l myr ;(:wk152 pxm0t distance will it slide before coming to a stop?

A. $15.0 \; m$

B. $30.0 \; m$

C. $375 \; m$

D. $750 \; m$

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

85#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 12-kg object is movingpy 1.-eqjd. ly on a rough, level surface. It has 24 J of kinetic energy. The friction force on it is a constantjl.y1ep-y .q d 0.50 N. How far will it slide?

A. $2.0 \; m$

B. $12 \; m$

C. $24 \; m$

D. $48 \; m$

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

86#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A force of 10 N is appl 4h k4sfnarx3 jp23(j2* cbcxhied horizontally to a 2.0-kg mass on a level surface. The coefficient of kinetic friction between the mass and the surface is 0.20h x3cc2fjsjbxr 4p *k2 4a3(nh. If the mass is moved a distance of 10 m, what is the change in its kinetic energy?

A. $20 \; J$

B. $39 \; J$

C. $46 \; J$

D. $61 \; J$

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

87#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 60-kg skier starts from rest from the top of a 50-mr,sl2 c,u 7tgsb9znv: high slope. If the work done by friction tn : 7lbzrvu9,sc 2,gsis $-6.0 \times 10^{3} \; J$, what is the speed of the skier on reaching the bottom of the slope?

A. 17 m/s

B. 24 m/s

C. 34 m/s

D. 31 m/s

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

88#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

An 800-N box is pushed up an inclined plane. Thc g g6nb3c+h)ze plane is 4.0 m long and rises 2.0 m. It requires 3200 J of wor6cn z)g c3g+hbk to get the box to the top of the plane. What was the magnitude of the average friction force on the box?

A. $0 \; N$

B. non-zero, but less than 400 N

C. $400 \; N$

D. greater than 400 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

标记此题

89#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 2.0-kg mass is releasedz v cbd++ :iut)h)lrv 4z6mumji:l69d from rest at the top of a plane inclined at 20e above horizontal. The coefficient of kinetic friction between the mass and the plane is 0.20. What will be the speed of the mass after sliding 4.0 mldm6 v+9bcim:+zilh :4v t z)) jduur6 along the plane?

A. 2.2 m/s

B. 3.0 m/s

C. 3.5 m/s

D. 5.2 m/s

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

本习题练习全部题目来源于题库网 (https://tiku.one)，学生可自助刷题练习，扫右侧二维码加微信，获取学习资料，答疑辅导
教师可以抽题组卷或一键复制他人试卷，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

90#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 30.0-N stone is dropped from a height of 10.0 m, and strikes the groundz0cwa8 (:efua with a velocity of 7.00 m/s. What average force:ue az8(c0a fw of air friction acts on it as it falls?

A. $22.5 \; N$

B. $75.0 \; N$

C. $225 \; N$

D. $293 \; N$

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

标记此题

91#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

At what rate is a 60.0-kg boy using energy when he runs up a flight of stai(;.s uzt (xsdnrs 10.s(xud(.; n zts0-m high, in
8.00 s?

A. $75.0 \; W$

B. $735 \; W$

C. $4.80 \; kW$

D. $48 \; W$

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

92#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 10-N force is needed to move an obje5ash bd1k+1a kct with a constant velocity of 5.0 m/s. What power mustd1s+5hbk1a ak be delivered to the object by the force?

A. $0.50 \; W$

B. $1.0 \; W$

C. $50 \; W$

D. $100 \; W$

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

93#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

How many joules of eo6da.h1 uxzszda5.,ynergy are used by a 1.0 hp motor that runs for 1.0 hr? (1 hp = ud a,sxoyz.5.hd16az746 W)

A. $3.6 \times 10^{3} \; J$

B. $2.7 \times 10^{6} \; J$

C. $4.5 \times 10^{4} \; J$

D. $4.8 \; J$

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

94#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A cyclist does work at the rate of 500 W while 0g-(c okoc *2ja mv(ai++jzr ariding. How much force does her foot push with when she is traveling at 8.0 mcajm( k oag*0 ( j-zicavr+2+o/s?

A. $31 \; N$

B. $63 \; N$

C. $80 \; N$

D. $4000 \; N$

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

标记此题

95#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1500-kg car accelerates from 0 toa.mw*y1kq wz ip84. by73zu kv 25 m/s in 7.0 s. What is the average power delivered by the engine? (1 hp = 7*.3 7.ib41qywum kvyzwp8 kaz46 W)

A. $60 \; hp$

B. $70 \; hp$

C. $80 \; hp$

D. $90 \; hp$

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

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	44	45	46	47	48	49	50
51	52	53	54	55	56	57	58	59	60
61	62	63	64	65	66	67	68	69	70
71	72	73	74	75	76	77	78	79	80
81	82	83	84	85	86	87	88	89	90
91	92	93	94	95

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	44	45	46	47	48	49	50
51	52	53	54	55	56	57	58	59	60
61	62	63	64	65	66	67	68	69	70
71	72	73	74	75	76	77	78	79	80
81	82	83	84	85	86	87	88	89	90
91	92	93	94	95

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	44	45	46	47	48	49	50
51	52	53	54	55	56	57	58	59	60
61	62	63	64	65	66	67	68	69	70
71	72	73	74	75	76	77	78	79	80
81	82	83	84	85	86	87	88	89	90
91	92	93	94	95