题目

问答句连线。1. Where do you live? A. I am wrapping presents.2. What are you doing?B. Yes, he is.3. Is he a teacher? C. I live at 25 Yunan Street.4. What do you do at home? D. I clean the windows.5. Is there a bookshop here? E. Yes, there is. 答案：【答案】1-5 C A B D E【解析】略如图所示，一静电计与锌板相连，在A处用一紫外灯照射锌板，关灯后，指针保持一定偏角．(1)现用一带负电的金属小球靠近锌板，则静电计的指针偏角将________．(填增大、减小或不变)(2)使静电计指针回到零，再用相同强度的钠灯发出的黄光照射锌板，静电计的指针无偏转．那么，若改用强度更大的红外灯照射锌板，可观察到静电计指针________(填有或无)偏转．