Physics Unit7: Linear Momentum - 51fly国际课程 (51fly.win)

1#

What is the SI unit of / p)kl, 0ml 2at,auuivmomentum?

A. Nm

B. N/s

C. Ns

D. 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

2#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

When a cannon fires a cannonball, the cannon will recoil ba-7mlbzg 8sl 4tjm5gs6ckward because the

A. energy of the cannonball and cannon is conserved.

B. momentum of the cannonball and cannon is conserved.

C. energy of the cannon is greater than the energy of the cannonball.

D. momentum of the cannon is greater than the energy of the cannonball.

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

3#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A freight car moves along a frictionless level railroad track at cons34 oxvozh0bp) tant speed. The car is open on top. A large load of coal is suddenly dumped into the car. What happens to the velocity of the car?p4z)30boohv x

A. It increases.

B. It remains the same.

C. It decreases.

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

A child falls sideways off a sled while sledding on frictionless ice. Whj rzzk3pvs7a(,7e q (hiafd/* oa1*jyat happens to the velocity vh(odje*,3j1spqzfa*ya/a z7 (7ikr of the sled?

A. It increases.

B. It remains the same.

C. It decreases.

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

5#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A rubber ball and a lump of putty have equal masso-+ 3i2i zryqr 2qvsi6. They are thrown with equal speed against a wall. The ball bounces back with nearly the same speed with which it hitrziqovs +y6ri 2iq23 -. The putty sticks to the wall. Which objects experiences the greater momentum change?

A. the ball

B. the putty

C. Both experience the same momentum change.

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

6#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A sailboat of mass m is moving with a momentum p. How would you represent its k n/ukr, :v*su65kiaf ainetic energy in term,6 5kaavsn u/ukfi:r* s of these two quantities?

A. $p^2/2m$

B. $\frac{1}{2} mp^2$

C. $mp$

D. $\frac{1}{2} mp$

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

If you pitch a baseball with twice the kinensc9p3r 0vp g)42evm ktic energy you gave it in the previous pitch, thm )nvpve 2r4kgsc0p93 e magnitude of its momentum is

A. the same.

B. 1.41 times as much.

C. doubled.

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

8#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State Newton's secondylz/sgf ) lyp -va.8*k law in terms of momentum.

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

9#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State the law of conservationsx gl7 vqzg tli .5v9*c.yij;) of momentum.

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

10#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The area under the curve on a Force versus time (F vs. t) g/+b022gvmh/xx*4anb i(+ gpni/o cr of:he teraph represents

A. impulse.

B. momentum.

C. work.

D. kinetic 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

标记此题

11#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Which of the following is an ailfn .-7vlnq65g jb:l ccurate statement?

A. The momentum of a projectile is constant.

B. The momentum of a moving object is constant.

C. If an object is acted on by a non-zero net external force, its momentum will not remain constant.

D. If the kinetic energy of an object is doubled, its momentum will also double.

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51fly国际课程 (https://51fly.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

12#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A small car meshes with a lf2 u-05 *egosvi)kokbarge truck in a head-on collision. Which of the following statements concerning the magnitude0 gskk2uovbeo- *f i5) of the average collision force is correct?

A. The truck experiences the greater average force.

B. The small car experiences the greater average force.

C. The small car and the truck experience the same average force.

D. It is impossible to tell since the masses and velocities are not 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

13#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two equal mass balls (one red and the other blue) are droppe kwut,ws d2zzijba3q49 gc3 4c)b7h6fd from the same height, and rebound off the floor. The red6 ij h w)9zwg ba443zu,fbqdt37ck2sc ball rebounds to a higher position. Which ball is subjected to the greater magnitude of impulse during its collision with the floor?

A. It's impossible to tell since the time intervals and forces are unknown.

B. Both balls were subjected to the same magnitude impulse.

C. the blue ball

D. the red 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

14#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A Ping-Pong ball moving east at a spg1(xo wdmyg1+ eed of 4 m/s, collides with a stationary bowling ball. The Ping-Pong ball bounces back to(mdy g wo1+x1g the west, and the bowling ball moves very slowly to the east. Which object experiences the greater magnitude impulse during the collision?

A. Neither; both experienced the same magnitude impulse.

B. the Ping-Pong ball

C. the bowling ball

D. It's impossible to tell since the velocities after the collision are unknown.

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

Two objects collide and bounce off each*ef/,k,e en5q hpewy 7 other. Linear momentum

A. is definitely conserved.

B. is definitely not conserved.

C. is conserved only if the collision is elastic.

D. is conserved only if the environment is frictionless.

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

16#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 3.0-kg object moves to the right at 4.r-7 gk8): j id/dgmstr0 m/s. It collides head-on with a 6.0-kg object moving :tg k-jrimd7dr)8 sg/to the left at 2.0 m/s. Which statement is correct?

A. The total momentum both before and after the collision is 24 kgm/s.

B. The total momentum before the collision is 24 kgm/s, and after the collision is 0 kgm/s.

C. The total momentum both before and after the collision is zero.

D. None of the above is true.

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

A 100-kg football linebacker moving at 2.0 m/s tackles headp-s .lf/1-j a292pdcmiq owwo-on an 80-kg halfback rlm.pjp29ifa-q s/2w -1odc w ounning
3.1 m/s. Neglecting the effects due to digging in of cleats,

A. the linebacker will drive the halfback backward.

B. the halfback will drive the linebacker backward.

C. neither player will drive the other backward.

D. this is a simple example of an elastic collision.

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

In an elastic collision, if the mome/p ff z9k1p9jnntum is conserved, then which of the following statements is trk/ 9zn1jpff9pue about kinetic energy?

A. Kinetic energy is also conserved.

B. Kinetic energy is gained.

C. Kinetic energy is lost.

D. 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

19#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

When is kinetic energy consetbz r.h7a0euj(mrc)pz; v 3z( rved?

A. in elastic collisions

B. in inelastic collisions

C. in any collision in which the objects do not stick together

D. in all collisions

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

In a game of pool, the white cue ball hits the #5 ball and stops, while thei dh*ysd::)2s9 3p duhetlz4g #5 ball moves away with the same velocity as the cue ball hhe lpi s4*d:d9 gd3 uzth2)s:yad originally. The type of collision is

A. elastic.

B. inelastic.

C. completely inelastic.

D. any of the above, depending on the mass of the balls.

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51fly国际课程 (https://51fly.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

21#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

When a light beach ba.5clsh cke. *zll rolling with a speed of 6.0 m/s collides with a heavy exer *zlekc.h5 .cscise ball at rest, the beach ball's speed after the collision will be, approximately,

A. 0.

B. 3.0 m/s.

C. 6.0 m/s.

D. 12 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

22#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A golf ball traveling 3.0 m/s to the right collides in a head-on n/g3sn x- q5mfu swi5f9w.,cncollision with a stationary bowling ball in a friction-nc u imss.g 95nfqnxf3ww5-/,free environment. If the collision is almost perfectly elastic, the speed of the golf ball immediately after the collision is

A. slightly less than 3.0 m/s.

B. slightly greater than 3.0 m/s.

C. equal to 3.0 m/s.

D. much less than 3.0 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

23#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A rubber ball with a speed j j 9x5x7yin0af; n7siof 5.0 m/s collides head-on elastically with an identical ball at rest. What is the speed of the initially stopped ball after the col09 y fixai j7snj5n7x;lision?

A. zero

B. 1.0 m/s

C. 2.5 m/s

D. 5.0 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

24#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A very heavy object moving wiyth, 6h. e ,xpfn,;psyfce g-/(4fmlwth speed v collides head-on with a very light object at rest. The collision is elastic, and there is no friction. The heavy object barely slows down. What is the speed of the light object afterm.p-ff/p(6gywc elt, e4n hhxfys , ,; the collision?

A. nearly v

B. nearly 2v

C. nearly 3v

D. nearly infinite

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51fly国际课程 (https://51fly.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

25#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A very light object movin8qos-y i 5ti( 9hh :nq3zxsix.g with speed v collides head-on with a very heavy object at rest, in zhs9. 5iixyi:(q q t8 xhson3-a frictionless environment. The collision is almost perfectly elastic. The speed of the heavy object after the collision is

A. slightly greater than v.

B. equal to v.

C. slightly less than v.

D. much less than v.

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

A red ball with a velocity of +3*m 8to yzsej k2ct- 08ywxm8u48z )mkv.0 m/s collides head-on with a yellow ball of equal mass moving with a velocity of o smwk jmx-z8z 48v*ey0c2t8)yut 8km-2.0 m/s. What is the velocity of the yellow ball after the collision?

A. zero

B. +3.0 m/s

C. -2.0 m/s

D. +5.0 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

27#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A very heavy object moving with velocity v collides head-on with ag-bx7bl fu1l8 very light object moving with velocity -v. The collision is elastic, and there is no friction. The heavy object barely slows db-bu7xgll 18 fown. What is the speed of the light object after the collision?

A. nearly v

B. nearly 2v

C. nearly 3v

D. nearly infinite

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

In an inelastic collision, if the momentumy 0 4oozmg5k-e is conserved, then which of the following statements z okg e0-y45omis true about kinetic energy?

A. Kinetic energy is also conserved.

B. Kinetic energy is gained.

C. Kinetic energy is lost.

D. 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

29#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two objects collide and stick together. Kinetic s q 9m,wquqak703eciznp7e9 cn 2 k6/nenergy

A. is definitely conserved.

B. is definitely not conserved.

C. is conserved only if the collision is elastic.

D. is conserved only if the environment is frictionless.

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51fly国际课程 (https://51fly.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

30#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 3.0-kg object moves to the right at 4.0 m/s. It collides in a perfectly itn5c,m z7araj5xxp y jq.0ry,uv )3-vnelastic collision withrj5t-x, .arvu y37yzcn,qj)vmx0a p5 a
6.1 kg object moving to the left at 2.0 m/s. What is the total kinetic energy after the collision?

A. $72 \; J$

B. $36 \; J$

C. $24 \; J$

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

31#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A small object collides with a large object and sticks. Which object experi5:n *n3l e-zes au-( ;7psqya1rhkhrcences the larger magnitude of momentuzh1 ph*e-r;s re3 ny usnc5ka:aq7 -(lm change?

A. the large object

B. the small object

C. Both objects experience the same magnitude of momentum change.

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

32#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

In a game of pool, the whib-n, droax*a b(nq2(sblqt-6i)zz )f te cue ball hits the #9 ball and is deflected at a $35^{\circ}$ angle to the original line of motion. What is the angle of deflection below the original line of motion for the #9 ball?

A. $35^{\circ}$

B. $55^{\circ}$

C. $75^{\circ}$

D. $90^{\circ}$

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

Consider two unequal masses7zx6 tg5v :x(qhoo .gc, M and m. Which of the following statements is false cvo(z5g.6xq tg xo:h7?

A. The center of mass lies on the line joining the centers of each mass.

B. The center of mass is closer to the larger mass.

C. It is possible for the center of mass to lie within one of the objects.

D. If a uniform rod of mass m were to join the two masses, this would not alter the position of the center of mass of the system without the rod present.

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

Which of the following is a false statemy bc;2pw)hn*a 7u1j luent?

A. For a uniform symmetric object, the center of mass is at the center of symmetry.

B. For an object on the surface of the Earth, the center of gravity and the center of mass are the same point.

C. The center of mass of an object must lie within the object.

D. The center of gravity of an object may be thought of as the "balance 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

35#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Tightrope walkers walk with a long flex) ri qf 7ys/azlgqz *q(8-hv;o/ n7vsiible rod in order to

A. increase their total weight.

B. allow both hands to hold onto something.

C. lower their center of mass.

D. move faster along the rope.

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 plane, flying horizontally, releases a bomb, which explodes before hitting rpxsp) 2/i3jr the ground. Neglecti/p23 pjsrr xi)ng air resistance, the center of mass of the bomb fragments, just after the explosion

A. is zero.

B. moves horizontally.

C. moves vertically.

D. moves along a parabolic path.

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

Two cars collide head-on on a level friction-free road. T8pf tql k,3d6nhe collision was completely inelastic and both cars quickly came to rest during the collision. What is true about the velocity of this system's center of mass 3t6d,f8p nklq?

A. It was always zero.

B. It was never zero.

C. It was not zero, but ended up zero.

D. 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

38#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

State Newton's second law for a system of particl)h si .8oelnx6es.

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

39#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

What is the momentum of a 2000-kg truck tr.1;j*; :lezjjm a;c3.t hks 7fwvjsxgaveling at 35 m/s?

A. $57 \; kg \cdot m/s$

B. $3.5 \times 10^{4} \; kg \cdot m/s$

C. $7.0 \times 10^{4} \; kg \cdot m/s$

D. $7.0 \times 10^{5} \; kg \cdot m/s$

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

40#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1200-kg ferryboat is moving south at 20 iog1zt kf,2hyv .m- 0tm/s. What is the magnitude of its mome ,m.fgyh1-zikv ot20 tntum?

A. $1.7 \times 10^{-3} \; kg \cdot m/s$

B. $6.0 \times 10^{2} \; kg \cdot m/s$

C. $2.4 \times 10^{3} \; kg \cdot m/s$

D. $2.4 \times 10^{4} \; kg \cdot m/s$

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

41#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A ball of mass 0.10 kg is dropped from a height of 12 m. aq 116 7ohbmvy;1be hb Its momentum when it strikes th b1vbh;abo1 1hqemy76e ground is

A. 1.5 kgm/s.

B. 1.8 kgm/s.

C. 2.4 kgm/s.

D. 4.8 kgm/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

42#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two identical 1500-kg cars are moving perpendic4-x fsuf kq9r:mfb- 2wular to each other. One moves with a speed of 25 m/s due north and ts9rwf -qfbxf u:-4 2kmhe other moves at 15 m/s due east. What is the total momentum of the system?

A. $4.4 \times 10^{4} \; kg \cdot m/s$ at $31^{\circ}$ N of E

B. $4.4 \times 10^{4} \; kg \cdot m/s$ at $59^{\circ}$ N of E

C. $6.0 \times 10^{4} \; kg \cdot m/s$ at $31^{\circ}$ N of E

D. $6.0 \times 10^{4} \; kg \cdot m/s$ at $59^{\circ}$ N of E

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51fly国际课程 (https://51fly.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

A handball of mass 0.10 kg, traveling horizontally at 30 m/s, strikes a wall5nmt 1li+xg g; and rebounds at 24 m/s. What is the change in the ;tn5mgl1+gxi momentum of the ball?

A. 0.60 kgm/s

B. 1.2 kgm/s

C. 5.4 kgm/s

D. 72 kgm/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

44#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 0.060-kg tennis ball, initially moving at a spy r8j7xn t31pbeed of 12 m/s, is struck by a racket causing it to rebound in the opposite direction at a speed of 18 m/s. What is the change inrx ty73 1jnp8b momentum of the ball?

A. 0.36 kgm/s

B. 0.72 kgm/s

C. 1.1 kgm/s

D. 1.8 kgm/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

45#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 50-kg pitching machine (excluding the baseball) is places6bqk gev * pxba)4 nr,412jvxd on a frozen pond. The machine fires a 0.40-kg baseball with a speed of 35 m/s in the horizontal direction. What is th*ge,vjsa4qn2r )b 6bk1vp x4xe recoil speed of the pitching machine? (Assume negligible friction.)

A. 0.14 m/s

B. 0.28 m/s

C. 0.70 m/s

D. $4.4 \times 10^{3} \; m/s$

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

46#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 70-kg astronaut is space-walking outside the space capsulerm8.zjumtakhw ox7 7 )zt *c82 nml6*c and is stationary when the tether line breaks. As a means of returning to the capsule he throws his 2.0-kg space hammer at a spza 2mo7xn w6jkcr)uz8m* t *h.tl m7c8eed of 14 m/s away from the capsule. At what speed does the astronaut move toward the capsule?

A. 0.40 m/s

B. 1.5 m/s

C. 3.5 m/s

D. 5.0 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

47#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A small object with mowjqjah 9 z(69h- u:zp td9f:uomentum 5.0 kgm/s approaches head-on a large object at rest. The small object bounces straight back with a momtfh9z6w9d :: aqp(uujz jo-9hentum of magnitude 4.0 kgm/s. What is the magnitude of the large object's momentum change?

A. 9.0 kgm/s

B. 5.0 kgm/s

C. 4.0 kgm/s

D. 1.0 kgm/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

48#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

You (50-kg mass) skate on ice at 4.0 m/s to greet your friend (40-knbscg;+i-)ed vd n3 + 7(vycmng mass), who is standing still, with open)+ vb(cdm iy+-;3nc d7ngsv en arms. As you collide, while holding each other, with what speed do you both move off together?

A. zero

B. 2.2 m/s

C. 5.0 m/s

D. 23 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

49#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A car of mass 1000 kg moves to the rjigryv qod(,;lq q.*)ight along a level, straight road at a speed of 6.0 m/s. It collides directly with a stopped motorcycle of mass 200 kg. What is the total momentum after the collq;q d. (*l oqg,jrvi)yision?

A. zero

B. 6000 kgm/s to the right

C. 2000 kgm/s to the right

D. 10,000 kgm/s to the right

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51fly国际课程 (https://51fly.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

50#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1000-kg car traveling at 25 m/s runs into the rear of a stoppswthu9w :g zj04(h 6hw,vwo3med car that has a mass of 1500 kg and they stick together. What,h wt :sozjwu94( ghw 3m0v6hw is the speed of the cars after the collision?

A. 5.0 m/s

B. 10 m/s

C. 15 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

51#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A railroad freight car, mass 15,000f,x.biu1 )ovo* l vppf2f 4j)e kg, is allowed to coast along a level track at a speed of 2.0 m/s. It collides and couples with a 50,000-kg second car, initially at rest and with brakes released. What u.p,pi1b *4 2j))exvf fvfoolis the speed of the two cars after coupling?

A. 0.46 m/s

B. 0.60 m/s

C. 1.2 m/s

D. 1.8 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

52#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A railroad car, of mass 200 kg, rolls with negligible friction 71c3)h 7aauirau o t,eon a horizontal track with a speed of 10 m/s. A 70-kg stunt man drops straight down a distanc)c1 atu7r o3u hiea7a,e of 4.0 m, and lands in the car. How fast will the car be moving after this happens?

A. 2.8 m/s

B. 4.7 m/s

C. 7.4 m/s

D. 10 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

53#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 60-kg person walks on a 100-kg log at the rate of 0.80 m/s (with res( r+5;,oid ke.gzahs xpect to the log). With what speed does the log move, with respect to the shorxhs+rd;zo gk5e.i,a (e?

A. 0.24 m/s

B. 0.30 m/s

C. 0.48 m/s

D. 0.60 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

54#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 4.0-N force acts for 3.0 s on an object. The force suddenly itc1ja5u:n5z c et)jb 6nc9 yc)9mxov:ncreases to 15 N and acts for one more second. What impulse was imparted by these forces to the ot:n cceca5jzub: c tny1)596 j9xmv)object?

A. $12 \; N \cdot s$

B. $15 \; N \cdot s$

C. $19 \; N \cdot s$

D. $27 \; N \cdot s$

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

55#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A constant 9.0-N net force acts for 2.0 s on a 6.0-kg objepl28y.y7wypyv - wwk3ct. What is the object's change of velocity 2 .kp y8wp3w-ywyvy7l?

A. 3.0 m/s

B. 9.0 m/s

C. 27 m/s

D. 110 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

56#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 2000-kg car, traveling to the right at 30 m/s, collides with a brick wall and em)dmef7c75amawbs yf5, w8 (comes to rest in 0.20 s. What is m7)5ws8, mm 5fbawey acdf( e7the average force the car exerts on the wall?

A. 12,000 N to the right

B. 300,000 N to the right

C. 60,000 N to the right

D. 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

57#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 2.0-kg softball is pitch2ftuna)irq) c7(gq s w.s5b .red to you at 20 m/s. You hit the ball back along the same path, and at the same speed. If the bat was in contact with the ball for 0.10 s, what is the magniti 7qacbsf. ))qsu5 .2wtgr (rnude of the average force the bat exerted?

A. zero

B. $40 \; N$

C. $400 \; N$

D. $800 \; N$

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

58#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 0.10-kg ball is dropped onto a table top. The speeds of the;rk 5b4z b/mvxrhchnm(rim0m 5ba-)/ ball right before and right after hitting the table top are 5.0 m/s and 4.0 m/s, respectively. If the collision between the ball and the table top lasts 0.15 s, what is the maghmb m //-5rnm5bh4xm )ck0rb aivz;(rnitude of the average force exerted on the ball by the table top?

A. $0.67 \; N$

B. $1.3 \; N$

C. $3.0 \; N$

D. $6.0 \; N$

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

59#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A machine gun, of mass 35.0 kg, fires 50.0-gram bullets, with a muzzx2 q fe4 dycakef,l- lf:0s/9nle velocity of 750 m/s, 4lc kl f2:fysq,d x-eanf/9e0at the rate of 300 rounds per minute. What is the average force exerted on the machine gun mount?

A. $94.0 \; N$

B. $188 \; N$

C. $219 \; N$

D. $438 \; N$

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

60#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A fire hose is turned on the door of a burning building inr69ca,; l fdb*so kv3v order to knock the door down. This requires a force of 1000 N. If the hose delivers 40 kg per second, what is the minimum velocity of the stream needed, assuming the wvk cfb6r 9d;*las,v3o ater doesn't bounce back?

A. 15 m/s

B. 20 m/s

C. 25 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

61#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Water runs out of a h +ehz 8(hnj0:)mw )wd gia8nunorizontal drainpipe at the rate of 120 kg per minute. It falls 3.20 m to the ground. Assuming the water doesn't splash up, what average force does it exert on am e(:u+nhz )nn)ijh 88 0gdwwthe ground?

A. $6.20 \; N$

B. $12.0 \; N$

C. $15.8 \; N$

D. $19.6 \; N$

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51fly国际课程 (https://51fly.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

62#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A toy rocket, of mass 0.12 kg, aq-v p,0fu zlf.chieves a velocity of 40 m/s after 3.0 s, when fired straight up. What average thrust for.,qp -lvzuf f0ce does the rocket engine exert?

A. $1.2 \; N$

B. $1.6 \; N$

C. $2.8 \; N$

D. $4.4 \; N$

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

63#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two astronauts, of masses 60 kg and 80 v6+c j -8smt0eriz tyi5dfs .1kg, are initially at rest in outer space. They push each other apart. What is their separation after the lighter astronaut has moved 12s+8mt5ii1esc r0ytvfzd6 - j. m?

A. $15 \; m$

B. $18 \; m$

C. $21 \; m$

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

64#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 3.0-kg object moves tp tgim,7ddo)8is+*pf0bxyvh+ ;6tzx0 nf5yl o the right with a speed of 2.0 m/s. It collides in a perfectly elastlo *i8tnpg+ xbzv0xsdpfd 7 y0+;mfi 6h,5yt)ic collision with a 6.0-kg object moving to the left at 1.0 m/s. What is the total kinetic energy after the collision?

A. $9.0 \; J$

B. $6.0 \; J$

C. $3.0 \; J$

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

65#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 0.10-kg object with a velocity y87zvd1z/r c pof 0.20 m/s in the +x direction makes a head-on elastic collision with a 0.15 kg object initially at z7d8cvz/ 1pyr rest. What is the final velocity of the 0.10-kg object after collision?

A. -0.16 m/s

B. +0.16 m/s

C. -0.040 m/s

D. +0.040 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

66#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 10.0-g bullet moving at 300 m/s is fired 9dfj / ;frnefn/7w-rld h7 *dhinto a 1.00-kg block at rest. The bullet emerges (the bullet does not get embedded in the block) with half of its original spe/d* fn 7dwlhrdf -hef9 ;rn/j7ed. What is the velocity of the block right after the collision?

A. 1.50 m/s

B. 2.97 m/s

C. 3.00 m/s

D. 273 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

67#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A proton, of mass m, at *re/wep*mkngqe d f /7q/1+ do+b4ade rest, is struck head-on by an alpha-particle (which consists of 2 protons and 2 neutrons) moving at speed v. If the collision is completely elastic, what speed will the alpha-particle have after the collision? (Assume the neutron's mass equals the pmaq+f4/gne1+r*ed/ 7 oq ebdpedk/*w roton's mass.)

A. zero

B. 2v/3

C. 3v/5

D. 5v/3

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 50-gram ball moving +10 m/s collides head-on with a stationary ball 8oz u+rhssfzrg/;w/o7e hg0drg-9 :9w9lpt eof mass 100 g. The collision is elastic. What is the speedle9/esrzdpzo gws:r 9 g+uh 0;-h7r /go9f8wt of each ball immediately after the collision?

A. -3.3 m/s and +6.7 m/s

B. +3.3 m/s and -6.7 m/s

C. -6.7 m/s and +3.3 m/s

D. +6.7 m/s and -3.3 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

69#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

A ball of mass 400 g moving toward the east with a lq)791qy+ qqy*axjueese -/ xspeed of 3.70 m/s collides head-on with a 200 7s9yqxlu1qjq*x a-eqee/) y+g ball sitting at rest. The collision is perfectly elastic.
(a) Determine the velocity of the first ball after the collision.
(b) Determine the velocity of the second ball after the collision.
(c) Is kinetic energy conserved in this collision?

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

70#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 2.0-kg mass moves with a speed of 5.0 m/s. It collides he6mjs-/(zat o qad-on with a 3.0 kg mass at rest. If the collision is perfectly inelastic, what is the speed o-m 6 zjt/oqa(sf the masses after the collision?

A. 10 m/s

B. 2.5 m/s

C. 2.0 m/s

D. 0, since the collision is inelastic

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

A 2.0-kg mass moving to the east at a speed of 4.0 m/s collides head hwpj(o6cq,c zp(- t zp6+jn/x-on in a perfectly inelastic collision with a stationary 2.0-kg mass. How much kinetic enerzcz(x6pt,jj q 6nh-pp( +cow/gy is lost during this collision?

A. $16 \; J$

B. $4.0 \; J$

C. $8.0 \; J$

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

本习题练习题目来源于51fly国际课程 (https://51fly.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

72#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A car of mass m, traveling with a velocity v, strikes a parked stationgd2e,d +cmg86/omdpf 8. zlx8zg1 dmf wagon, who's mass is 2m. The bumpers lock together in this head-on inelastic collision. What fractioz.mc fo8m ggxzfdg+ 6,8e /m82dpl1 ddn of the initial kinetic energy is lost in this collision?

A. 1/2

B. 1/3

C. 1/4

D. 2/3

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

73#

问答题 ( 1.0 分) 切至整卷模式搜藏此题

A 15-g bullet traveling 213 m/s in a vl +2cge8 c(d 0qra,p(m+v jmzjertical direction buries itself in a 2.4-kg block of wood a rest directly above it. As a result, the bullet/blod8(eza mmj qc,+r2j+0vc(pg lck combination moves vertically upward.
(a) Determine the velocity of the bullet/block combination at the point of impact.
(b) Determine the maximum height reached by the bullet/block combination.
(c) Is kinetic energy conserved in this collision?

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

74#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1500-kg car traveling at 90.0 km/h east p-hra y7i15nuvt28my:;ngyzug0d r2 46gh kf collides with a 3000-kg car traveling at 60.0 km/h south. The two cars stick together after the collision. (See Fig. 7-1.) What is the speedka m 80gzythnvyu6hf nu4i :2-r17rp5gy g2;d of the cars after collision?

本题所包含的其它图片:

A. 8.33 m/s

B. 13.9 m/s

C. 17.4 m/s

D. 21.7 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

75#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 1500-kg car traveling at 90.0 km/h east collides with a 300iuz1 n2aalv k ;:-5:9/msvvt vzrb5nv0-kg car traveling at 60.0 km/h southrtlvvm9: za u 1ivnsa/kvnv -5;2 b5z:. The two cars stick together after the collision. (See Fig. 7-1.) What is the direction of motion of the cars after collision?

本题所包含的其它图片:

A. $36.9^{\circ}$ S of E

B. $36.9^{\circ}$ E of S

C. $53.1^{\circ}$ S of E

D. $53.1^{\circ}$ E of 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

76#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Two objects move on a level frictionless surface. Object A mosj02zth . ijetf lj)1wy5) mp2ves east with a momentum of 24 kpm 2)h1.2l)yfjsw0jz5i j tt egm/s. Object B moves north with momentum 10 kgm/s. They make a perfectly inelastic collision. What is the magnitude of their combined momentum after the collision?

A. 14 kgm/s

B. 26 kgm/s

C. 34 kgm/s

D. cannot be determined without knowing masses and velocities

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 small bomb, of mass 10 kg, is moving toward the North witg5tb) n:q z.ygep /uy*h a velocity of 4.0 m/s. It explodey:b*un5 gep g.y/q)z ts into three fragments: a 5.0-kg fragment moving west with a speed of 8.0 m/s; a 4.0-kg fragment moving east with a speed of 10 m/s; and a third fragment with a mass of 1.0 kg. What is the velocity of the third fragment? (Neglect air friction.)

A. zero

B. 40 m/s north

C. 40 m/s south

D. 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

78#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 4.00-kg mass sits at the origin, and a 10.0-kg ma :xaf:p8ggs5xs vjw4qm b c:9;ss sits at x = + 21.0 m. Wher:jcf4gsxavw9p: :5s bxmg8 q;e is the center of mass on the x-axis?

A. +7.00 m

B. +10.5 m

C. +14.0 m

D. +15.0 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

79#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

The center of mass of j 55b -fq*i:vuaqnes ml11.dja two-particle system is at the origin. One particle is located at (3.0 m, 0) and has a mass of 2.0 kg. What is the location of the second masa 5eb.qn sd1lqj :j *vm1u-5ifs of 3.0 kg?

A. (-3.0 m, 0)

B. (-2.0 m, 0)

C. (2.0 m, 0)

D. (3.0 m, 0)

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51fly国际课程 (https://51fly.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

80#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Three masses are positioned as follow1cl92jp k 1o))(ke0vyurqumjpz 6 q* ps: 2.0 kg at (0, 0), 2.0 kg at (2.0, 0), and 4.0 kg at (2.0, 1.0). Determine the coordinates of the c16zm2 )19 rkupck0puejj*)yqovp(lq enter of mass.

A. (0.50, 1.5)

B. (1.5, 0.50)

C. (2.5, 1.5)

D. (2.5, 0.50)

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

81#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Three masses, 1.0 kg, 2.0 kg, and 3.0 kg, are located at (0, 0), (1.x ld9q/.6g 6bfy c vyka.-sqaod3ft, 20 m, 1.0 m), and (2.0 m, -2.0 m), respectivelyd -6.q.oy qgf 9acd/2bs kv3yf,a6xtl. What is the location of the center of mass of the system?

A. (1.3 m, 0.67 m)

B. (1.3 m, -0.67 m)

C. (-1.3 m, 0.67 m)

D. (-1.3 m, -0.67 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

本习题练习题目来源于51fly国际课程 (https://51fly.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

82#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

A 3.0-kg mass is positioned at (0, 8.0), and a 1.0-kg mass is positioned at (12,hsy6e1zv: 08f)wno ( )p:rivh gdmy q8 0). What are the coordinates of a 4.0-kg mass which will result in the center of mass of the system of three mas)hy 08p :y (we sdfhzmgrnvv)oi86:q1ses being located at the origin, (0, 0)?

A. (-3.0, -6.0)

B. (-12, -8.0)

C. (3.0, 6.0)

D. (-6.0, -3.0)

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

83#

单选题 ( 1.0 分) 切至整卷模式搜藏此题

Use Table 7-1 to calculate d 85s4d9wcy0;nhbaqfthe position of the CM of a whole leg including the foot when the leg is stretched straight out. Assume the persoshyfwc84a0 q5b9 n; ddn is 1.60 m tall.

本题所包含的其它图片:

A. 0.20 m above the bottom of the foot

B. 0.32 m above the bottom of the foot

C. 0.51 m above the bottom of the foot

D. 0.54 m above the bottom of the foot

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：

发帖咨询：

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	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

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

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