两定值电阻甲、乙中的电流与电压关系如图所示，甲的电阻为_________Ω；将甲和乙并联后接在电压为2.0V的电源两端，干路中的电流为___________A.
|
5 0.6
通过电阻的电流-电压关系图可以读出在一定电压下电流的大小，从而可以求出电阻的大小，如甲电阻两端的电压为2V时，电流为0.4A，根据欧姆定律可以求出电阻大小。当它们并联时，电压相等，总电流等于它们的电流之和，可以读出当电压为2V时甲、乙两电阻的电流，相加即为总电流。
【命题立意】本题综合考查了电阻的I-U图像及并联总电流的求法。
| 阅读下列短文，选择可以填入空白处的最佳选项。 | ||||
| My name is Martin. Years ago, I went to Michigan in the United States __1__ an exchange student. I wanted to improve my English and learn about the culture there. __2__, I learned something else: When you are in trouble, you should believe love is here and there. On the 26th of August, my host family __3__ me up from the airport in a big American car. In the car, I did not talk much __4__ my English was poor. And I tried to answer their questions fast and go to bed early. The first week at my new home was OK. The following weeks, I __5__ that the family was really strict and cold. One day, the son of the family __6__ a baby parrot as a gift. Later on, the bird was really sick. But the child told his mom it was because every night, when __7__ was sleeping, I poured some dirty water straight at the bird. My host mom __8__ the lie (谎言) of her son and my sad life there started. Then one day the parrot was __9__. I had to leave the home. The family all thought I killed it. __10__, I made more friends in the school and I could move to live with them. They gave me love when I was in trouble. Now, I visit them once or twice a year. | ||||
|