有一种测量人的体重的电子秤,其测量部分的原理如图中虚线框里的内容所示.它主要由四

题型:计算题

问题:

有一种测量人的体重的电子秤,其测量部分的原理如图中虚线框里的内容所示.它主要由四部分构成:踏板和压力杠杆OBA(可绕O 点转动)、定值电阻R0、压力传感器R(其电阻值会随所受压力大小发生变化,变化关系如下表)、显示质量大小的仪表(实质是一个量程为0~3V的电压表).已知OB: OA= 1:4,电源电压恒为3V,忽略踏板、压力杠杆的重力,g取 10N/kg.

(1)当踏板空载时,电压表的示数为0.75V,求定值电阻R0的大小.

(2)当某同学站在踏板上时,电压表显示为1.2V,此时压力传感器R的阻值多大?该同学体重是多少?

考点:欧姆定律及其应用杠杆的平衡条件
题型:计算题

有关糖原合成下列哪种说法是不正确的()

A.UDPG与引物非还原端形成α-1,4糖苷键

B.需α-1,4多聚葡萄糖作为引物

C.糖原合酶是关键酶

D.消耗ATP和UTP

E.胰岛素对糖原合酶有抑制作用

题型:计算题
I went to Beijing this National holiday, and it was an interesting experience of my life.
My friends told us that taking the “hard   16 ” to Beijing would be really terrible. So we didn’t know what to   17 . But we were pleasantly surprised when we finally boarded the   18 , which was relatively modern and   19 . During the 14-hour ride we ate peanuts and talked. It was not   20  at all.
It was morning when we arrived. We stepped out of the railway station, having sat in hard seats and not getting much   21 . However, we had energy. First, we tried to get return tickets to Shanghai, but the tickets seller   22  us that tickets would not be on   23  for another two days. We were a little worried about getting   24  , but we made up our minds to   25  for the hotel to put our bags down. After fighting our way   26  the “gypsy” taxi driver who tried to   27  one hundred yuan for the ride, we found another taxi and it   28  cost us thirty yuan to get   29  we had planned to go. When we reached the hotel, there was a window for airplane and train tickets.   30 , the man behind the counter could get tickets that day, which we   31 . The most important lesson about China I ever   32  is to get someone to do your work for you, and it seems to work out much   33 . We were not able to get tickets, but the   34  agents could.
While in Beijing we saw a lot of places of interest, most of which were very   35 . It was fun to be with thousands of people in one place. There aren’t any words to describe it.
小题1:
A.chairB.bedC.benchD.seat
小题2:
A.provide B.happenC.expectD.think
小题3:
A.planeB.trainC.shipD.bus
小题4:
A.cleanB.dirtyC.simpleD.long
小题5:
A.easyB.goodC.badD.hard
小题6:
A.trouble B.sleepC.foodD.help
小题7:
A.promisedB.persuadedC.advisedD.informed
小题8:
A.saleB.showC.dutyD.time
小题9:
A.behindB.outC.backD.through
小题10:
A.askB.startC.lookD.pay
小题11:
A.towardsB.intoC.pastD.across
小题12:
A.charge B.offerC.bargainD.share
小题13:
A.evenB.onlyC.alsoD.still
小题14:
A.whereB.whichC.whatD.how
小题15:
A.MeanwhileB.OtherwiseC.Therefore D.However
小题16:
A.couldn’tB.wouldn’tC.shouldn’tD.needn’t
小题17:
A.heardB.taughtC.gaveD.learned
小题18:
A.harder B.earlierC.easierD.later
小题19:
A.businessB.travelC.transportD.hotel
小题20:
A.interestingB.crowdedC.famousD.good
题型:计算题

在FANUC 18M CNC系统中,功能键描述正确的为()。

A.POS:现在位置显示键

B.OFFSET SETTING:设定和显示刀补值

C.MESSAGE:警示号码显示及设定

D.GRAPH:参数设定及显示,自我诊断资料显示

E.SYSTEM:画面显示功能

题型:计算题

骨髓增生极度活跃,粒红比例>5:1,原始粒细胞占有核细胞35%,考虑可能为

A.急性粒-单细胞白血病
B.慢性粒细胞白血病
C.急性粒细胞白血病
D.急性粒细胞白血病M2b型
E.粒细胞型类白血病反应

题型:计算题

中国矿业大学历经()次搬迁,()次易名。

A.14,11

B.12,14

C.11,14

D.12,16

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