题干

如图甲是灯泡L和电阻R的I-U关系图像,灯丝电阻受温度的影响,温度越高电阻越大.将L和R以两种不同的方式接在同一电源上,如图乙和丙.若乙图中U1︰U2= m,丙图中I1︰I2= n,则下列关系式中正确的是()


A:m=n           

B:m= 1n

C:m< 1n

D:m> 1n

上一题 下一题 0.0难度 选择题 更新时间:2019-01-09 10:10:31

答案(点此获取答案解析)

C

同类题1

    Jim, a successful businessman, told the experience of his childhood.
    When he was 12, his parents 1. He was alone and didn’t get on well with others. People always laughed 2 him. No one showed kindness (友善) to him. His only friend was a dog named Tige.
    One day as he walked down the street, a young lady was walking in front of him. Suddenly one of her bags dropped from her arms. As she stopped3, she dropped other bags. He came to help her.“Thank you, dear! You are a nice little boy!”She said kindly, smiling.
A special feeling came to him. These were 4 kind words he had ever heard. He watched her 5she went far away, and he whistled(吹口哨)to his dog and went directly to the river nearby.
    “Thank you, dear! You are a nice little boy!”he repeated the woman's words. Then in a low    6 he said to his dog,“You are a nice little dog!”Tige raised 7 ears as if(似乎)it understood.
    “Uh! Even a dog likes it!”he said,“Well, Tige, I won't say unkind words to you any more.”Tige waved its tail happily.
    The boy thought and thought. Finally he looked at himself in the river. He saw 8 but a dirty boy. He washed his face9. Again he looked. He saw a clean nice boy. He was amazed (震惊). From then on, he had a new life.
    After telling this, the businessman stopped for a while, and then he said,“Ladies and gentlemen, this is the very place where that kind woman planted in me the first seed (种子) of kindness. All of us should learn about kindness. 10a great power it has!” If you show kindness to others, you will be an able man.