直流弧焊机电流细调节,将可变电阻阻值调大,焊接电流增大。.

题型:判断题

问题:

直流弧焊机电流细调节,将可变电阻阻值调大,焊接电流增大。.

考点:焊工技能考试中级机械焊接工中级机械焊接工题库
题型:判断题

根据《合伙企业法》的规定,下列选项中,属于合伙人当然退伙的情形是()

A.未履行出资义务

B.个人丧失偿债能力

C.合伙协议约定的退伙事由出现

D.执行合伙企业事务时有不正当行为

题型:判断题

如图所示,两个绝缘斜面与绝缘水平面的夹角均为α=45°,水平面长d,斜面足够长,空间存在与水平方向成45°的匀强电场E,已知E=

2
mg
4q
.一质量为m、电荷量为q的带正电小物块,从右斜面上高为d的A点由静止释放,不计摩擦及物块转弯时损失的能量.小物块在B点的重力势能和电势能均取值为零.试求:

(1)小物块下滑至C点时的速度大小;

(2)在AB之间,小物块重力势能与动能相等点的位置高度h1

(3)除B点外,小物块重力势能与电势能相等点的位置高度h2

题型:判断题

在相同的时间内,某正弦交变电流通过一阻值为100 Ω的电阻产生的热量,与一电流为3A的直流电通过同一阻值的电阻产生的热量相等,则[ ]

A.此交变电流的有效值为3A,最大值为

B.此交变电流的有效值为,最大值为6A

C.电阻两端的交流电压的有效值为300 V,最大值为

D.电阻两端的交流电压的有效值为,最大值为600 V

题型:判断题

阅读理解。

     I have a seven-year-old son named John. He loves chocolates. He often takes chocolates instead of meals.

Therefore, he gets very bad teeth. The dentist (牙医) told me not to let him eat chocolates any more. But his

grandfather dotes on (宠爱) him. He often buys John chocolates even though he knows that they are bad for

teeth. I know that John is his only grandson, who is everything to him. I really don't want to make him

unhappy. Therefore, I always allow John to eat the chocolate his grandfather bought him.

    Yesterday evening I kissed John good night and asked him to say his prayers before going to bed, and then

I left his bedroom. A few minutes later, I heard John shouting word by word. "Tomorrow-is-my-birthday.

May-God-bring-me-a-big-box-of-chocolates." I went to his room and saw him kneeling on the ground

shouting out his prayers. I said, "Don't shout, John. Your Dad is sleeping now! God can hear you no matter

how softly you talk to him." Pointing to the next room where his grandpa sleeps, John said secretly, "My God

is sleeping. He can't hear me unless I wake him up."

1. Why does John's grandpa often buy John chocolates? [ ]

A. He doesn't know they are bad for his teeth

B. He loves John very much

C. He shows too much fondness for his grandson

D. He wants to make John happy

2. What did the boy do before going to bed that evening? [ ]

A. He knelt on the ground and prayed for God

B. He knelt on the ground and prayed to his grandpa for chocolates

C. He knelt on the ground and prayed for his grandpa

D. He knelt on the ground and prayed to God for chocolates

3.The sentence" Who is everything for him" means            . [ ]

A. who is his only grandson

B. who is a most important person to him

C. who is dearer to him than anything else

D. who is near and dear to him

4. The boy shouted out his prayers in order to            . [ ]

A. make God hear him

B. let his father know

C. wake up his grandpa

D. do what his father told him

题型:判断题

人类()的出现是产生人类秘书性活动的条件和基础,也是人类早期秘书性活动的标志。

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