欧姆定律体现了同一导体或同一段电路上同时存在的三个物理量：电_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题问答题

欧姆定律体现了同一导体或同一段电路上同时存在的三个物理量：电压U、电流I和电阻R之间的数量关系为，I=

U

R

或U=IR或R=

U

I

，知道任何两个量，可求第三个量．

结合课本相关知识，思考下列问题：

（1）欧姆定律数学表达式中各字母的含义．

（2）根据公式R=

U

I

，能不能说“电阻跟电压成正比，跟电流成反比”？

答案

答：（1）在欧姆定律表达式：I=

U

R

中，I表示通过导体的电流，U表示导体两端的电压，R表示导体电阻．

（2）导体电阻由导体材料、长度、横截面积决定，与导体两端电压与通过导体的电流无关，导体电阻在数值上等于导体两端电压与通过导体的电流之比，不能根据R=

U

I

认为“电阻跟电压成正比，跟电流成反比”．

完形填空

Section C

Directions: Read the following passage carefully and complete the passage by filling in each numbered blank with one word that fits the context.

According to The New Oxford Dictionary of English, frustration, by definition, means 48. ______ feeling of being upset or annoyed, especially because of inability to change or achieve something. Since frustration seems to 49.______ a negative feeling, some people may be temped to think that frustration is bad for people. 50. ______ , however, hold a different view. They believe that it is beneficial to people. They say frustration goes side 51. ______ side with success and that it inspires people to overcome hardships and difficulties and 52. ______ the final success. It is thus part of our life experience. So far as I’m 53. ______ , it is 54. ______ completely good nor completely bad. In our process of growing up, we may inevitably experience it. It is a test of our courage. If we let it control us, we may fall into the abyss (深渊) of serious psychological problems. 55. ______ if we harness (利用) it and take it as our inspiration, we may finally enjoy the glory of success.

问答题

认真阅读“给定资料”，简要回答下列两个问题。

“给定资料8”提到高考虚假加分问题，对这一问题你怎么看
要求：分析思考条理清楚，观点明确，字数不超过200字。