重为120N、底面积为0.1m2的物体在20N的水平拉力F作用下沿水平地面向右匀

题型:计算题

问题:

重为120N、底面积为0.1m2的物体在20N的水平拉力F作用下沿水平地面向右匀速运动了10m,用时20s。求:

(1)物体对地面的压强;

(2)物体所受摩擦力的大小;

(3)拉力所做的功和拉力的功率。

考点:压强的大小及其计算功率的计算平衡力与平衡状态
题型:计算题
集合A={x|x=2n+1,n∈Z},B={y|y=4k±1,k∈Z},则A与B的关系为(  )
A.A⊊BB.A⊋BC.A=BD.A≠B
题型:计算题
My tire was flat. And I was on a country road. When I      with the tire, a car pulled off the road behind me. I saw a male      and said, “Hey, do you need any help?”
  I literally was     . This young guy was dressed in black. Nearly everything imaginable was tattooed(纹身). When he asked to give me a     , I      someone sitting in his car. That      me. Thoughts of robberies flashed through my mind.
Then, it began to     . It hit like a waterfall and made it      to finish the tire change. With the car jacked(千斤顶托起) up, I was      to get in my car. “Get in my car” he insisted, “We’ll wait with you until the rain stops.” “No. I don’t need your help.” I said. “Come on. Get in.” he said as he      my arm and pulled me toward his car. “Oh, God, protect me!” I      to myself.
As I settled into the back seat, suddenly a delicate      came from the front seat of the car. “Are you all right?” “Yes, I am,” I replied with much      seeing an old woman there. “My name is Beatrice and this is my neighbor John. John takes me to visit my husband in a nursing home every day. He is a really nice guy.”
“John, I had thought you were, well, ah, you know I…” Embarrassment      my words. John laughed, “I often experienced      reaction. I actually thought about changing the way I look.      then I saw it as an opportunity to see others.”
He was right. What he wore outside was just a      of the world as he saw it, but what he wore      was the spirit of giving and caring the world he wanted to see. I never believed that I should       people by the way they dressed. I was     with myself for what I did.
The rain stopped and John and I changed the tire. As we shook hands I apologized for my stupidity.
小题1:
A.waitedB. repairedC. struggledD. continued
小题2:
A.turnedB. approachedC. boardedD.[ stopped
小题3:
A.delightedB. calmC. frightenedD. excited
小题4:
A.lookB. aidC. fineD. hand
小题5:
A.recognizedB. metC. noticedD. watched
小题6:
A.amazedB. attractedC. confusedD. concerned
小题7:
A.pourB. startC. fallD. break
小题8:
A.possibleB. necessaryC. unnecessaryD. impossible
小题9:
A.readyB. eagerC. unableD. unsuitable
小题10:
A. touchedB. graspedC. placedD. controlled
小题11:
A. thoughtB. expectedC. repliedD. cried
小题12:
A. toneB. voiceC. soundD. alarm
小题13:
A. reliefB. shockC. easeD. sorrow
小题14:
A. blockedB. stuckC. chokedD. struck
小题15:
A. helpfulB. shamefulC. abnormalD. unfriendly
小题16:
A. AndB. SoC. ButD. Or
小题17:
A. reflectionB. conclusionC. concernD. meaning
小题18:
A. aroundB. alongC. throughD. inside
小题19:
A. decideB. appreciateC. judgeD. sniff
小题20:
A. angryB. gratefulC. strictD. content
题型:计算题

食品安全法对食品检验机构从事检验工作的人员的检测能力和行为规范方面综合素质是如何规定的?

题型:计算题

肝细胞炎症临床可出现()。

A.溶血性黄疸

B.阻塞性黄疸

C.实质性黄疸

D.败血症

E.以上都是

题型:计算题

普通试井钢丝用于一般()起下仪器和井下工具。

A、油井、气井

B、油井、气井、水井

C、水井、气井

D、油井、水井

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