题目

在如图6-1-2所示的电路中，开关S是闭合的，现增大电容器A、B两极板间距，则下列说法正确的是（    ） 图6-1-2A.电容器的电容将增大，带电荷量增加            B.电容器的电容将减小，带电荷量增加C.电容器的电容将不变，带电荷量也不变         D.电容器的电容将减小，带电荷量不变 答案：思路解析：当增大电容器A、B极板间距时，由C= 知，其电容将减小，而电容器两极板间电压一定，由Q=CU知，电容器的带电荷量应减少，但由于二极管的单向导电性，其反向电阻无穷大，可认为断电，故阻止了正负电荷的中和，故其带电荷量不变.答案：DHow can we improve our spoken English ? The first and the most important thing is to believe1. （你自己）. You should always be 2. （充满的）of confidence, or you’ll never be able to improve your English. You should never 3. （失去）heart and never give up. Maybe you’re 4. （害怕的）of making mistakes, but you should think we are students and we are5. （学习）the language, there is no 6. （需要）to worry about anything. There is no problem that your pronunciation can’t be as 7. （好）as the native people because we are Chinese, and we don’t have 8. （机会）to foreign countries. You should believe the native speakers will not 9. （嘲笑）at you. If you are brave 10. （足够地）, you will certainly make progress quickly in your spoken English.