问题
选择题
有两段导体1和2，在相同的电压下，通过导体1的电流较大，通过导体2的电流较小，哪段导体的电阻大？（ ）
A．导体1的电阻大
B．导体2的电阻大
C．两段导体的电阻一样大
D．无法判断
答案
由题知，两段导体两端的电压相同，
∵I=
，I1＞I2，U R
∴R1＜R2．
故选B．
搜题请搜索小程序“爱下问搜题”
有两段导体1和2，在相同的电压下，通过导体1的电流较大，通过导体2的电流较小，哪段导体的电阻大？（ ）
A．导体1的电阻大
B．导体2的电阻大
C．两段导体的电阻一样大
D．无法判断
由题知，两段导体两端的电压相同，
∵I=
，I1＞I2，U R
∴R1＜R2．
故选B．
Mr. Black loved his daughter very much. Every day he spent all of his free time 1____ with her. One night, he had much work to do , 2____ couldn’t play with his daughter. In order to keep her 3____he found a map of the world in a magazine and cut it into pieces. When he 4___ , Helen came running to him and was ready to play. Mr. Black said he had 5_____ time to play right now. He told the girl to put the pieces of paper back together to a map of the world, and then they could both play. About half an hour later, Helen came to her father and said,“ Okay，it’s finished. Can we play now?” Mr. Black was surprised, saying, “That’s 6____. Let’s go and see.” And sure enough, there was the picture of the world, all put together, every 7____in its place. Mr. Black said, “That’s surprising! 8_____ did you do that?” Helen said, “It was 9____ .On the back of the page was a picture of a 10_____. When I put the man together, the whole world fell into place.”
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