小珊同学想把一只铭牌为“1.5V1.5W”的小灯泡接在电源电压为6V的_爱下问搜题

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问题问答题

小珊同学想把一只铭牌为“1.5V 1.5W”的小灯泡接在电源电压为6V的蓄电池上正常使用，请通过计算说明应串联一个多大的电阻？

答案

设应串联一个阻值为Rx的电阻，才能使它接在电压为6V的电源上正常使用．

U_x=U-U_L=6V-1.5V=4.5V，

I_L=

PL

UL

=

1.5W

1.5V

=1A，∵I_x=I_L=1A，

∴R_x=

Ux

Ix

=

4.5V

1A

=4.5Ω，

答：应串联一个4.5Ω的电阻．

填空题

腹膜炎治愈后，腹腔内多有不同程度的________，可发生________肠梗阻。

完形填空

My mother only had one eye. And because of this, I never wished her to show up in my school, being afraid that my classmates would     I had an ugly mother.
One day during elementary school, I was terribly ill. My mother came.
“Your mom only has one eye?!” asked some of my classmates. I was so     .
I wished my mother would just     from this world. “If you make me teased(嘲笑)，why don’t you just die?” I shouted at her, taking no notice of the sad look on her face. My mother just handed me some medicine and left without saying     .
At that time, I felt     to say what I always wanted to say, and I didn’t think I had hurt her feelings very much. That night I saw my mom     in her room, so quietly, as if she was afraid that she might     me. Even so, I hated her tears from one eye. I made a     : I must study hard and leave my mother.
Years later my dream came true. I was quite successful and lived     . I never thought of going back to see my “ugly” mother     one day I got a letter, which said, “My son… I’m sorry I only have one eye. When you were little, you got into a(n)     and lost your eye. As a mom, I couldn’t     watching you live with only one eye.       I gave you mine. I was never     with you and I never regretted(后悔) what I did because I     you…”
I cried out aloud. Only then did I realize how beautiful my mother was!

B．embarrassed

B．appointment