如图所示,一根细绳绕过光滑的定滑轮,两端分别系住A、B两物体,其质量M和m分别为

题型:问答题

问题:

如图所示,一根细绳绕过光滑的定滑轮,两端分别系住A、B两物体,其质量M和m分别为0.6㎏和0.4㎏,开始时用手托住A,使A、B处于同一高度,离地高度h为1m.重力加速度g取10m/s2

求:(1)当A物体由静止释放到落地时的速度(绳足够长,绳与滑轮的质量不计);

(2)B物体第一次上升过程中所达最高点离地高度.

考点:机械能守恒定律
题型:问答题

治疗真菌性 * * 炎,局部用药应首选( )

A.制霉菌素加二妙虎参煎
B.克林霉素加塌痒方
C.甲硝唑加二妙虎参煎
D.氟哌酸加苦参合剂
E.氯霉素加柴马洗剂

题型:问答题

患者男,53岁,间断发作上腹部疼痛15年,近一个月来出现呕吐症状并逐渐加重,呕吐物为隔餐所进食物,量大,体重减轻8kg。

该患者行体格检查时最可能发现()

A.腹部有胃型及蠕动波

B.口唇苍白

C.左侧锁骨上淋巴结可触及肿大

D.肛门指诊检查直肠前窝可触及有肿块

E.腹部触诊发现肿物

题型:问答题

西安事变对时局发展产生的最重要的影响是  [ ]

A.国共两党关系改善

B.抗日救亡运动高涨

C.抗日民族统一战线的初步形成

D.十年内战结束

题型:问答题

什么是市场支配地位?

题型:问答题

Questions


·Read the following passage and choose the best word for each space.
Do you want to send an e-mail message to the White House
Good luck.
In the past, (26) President Bush — or at least those assigned to read his mail — what was (27) your mind it was necessary only to sit down at a personal computer connected to the lnternet and (28) a note to president@ whitehouse.gov.
But this week, Tom Matzzie, an online organizer with the A.F.L.-C.I.O., discovered that (29) with the White House had become a bit more (30) . When Mr. Matzzie sent an e-mail protesting (31) a Bush administration policy, the message was bounced back With an automated reply, saying he had to send it again in a new way.
Under a system (32) on the White House Website (33) the first time last week, those who want to send a message to President Bush must now (34) as many as nine Web pages and (35) a detailed form that starts by asking whether the message sender supports White House policy (36) differs with it.
The white House says the new e-mail system is an effort to be more responsive (37) the public and offer the administration "real time" access (38) citizen comments.
Completing a message to the president also requires (39) a subject from the provided list, then entering a full name, organization, address and e-mail address. (40) the message is sent, the writer must wait for an automated response (41) his message, (42) whether the addressee intended to send the message. The message is delivered to the White House only after the person using that e-mail address (43) it.
"Over (44) , it’s a very cumbersome process," said Jakob Nielsen, an authority on Web design. "It’s probably designed deliberately to (45) on their e-mail.\

A. to choose B. of choosing C. choosing D. choice

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