题目

Mr. Peter Johnson, aged twenty-three, battled for half an hour to escape from his trapped car yesterday when it landed upside down in three feet of water. Mr. Johnson took the only escape route——through the boot(行李箱). Mr. Johnson’s car had finished up in a ditch(沟渠) at Romney Marsin, Kent, after skidding on ice and hitting a bank. “Fortunately, the water began to come in only slowly,” Mr. Johnson said, “I couldn’t force the doors because they were jammed against the walls of the ditch and dared not open the windows because I knew water would come flooding in.”3．一个小灯泡的额定电压为2.0V，额定电流约为0.5A，选用下列实验器材进行实验，并利用实验数据描绘和研究小灯泡的伏安特性图线．A．电源E：电动势为3.0V，内阻不计；B．电压表V1：量程为0-3V，内阻约为1kΩ；C．电压表V2：量程为0-15V，内阻约为4kΩ；D．电流表A1：量程为0-3A，内阻约为0.1Ω；E．电流表A2：量程为0-0.6A，内阻约为0.6Ω；F．滑动变阻器R1：最大阻值为15Ω，额定电流为1.0A；G．滑动变阻器R2：最大阻值为150Ω，额定电流为1.0A；H．开关S，导线若干．实验得到如下数据（I和U分别表示通过小灯泡的电流和加在小灯泡两端的电压）：I/A0.000.160.250.300.340.400.450.50U/V0.000.200.400.600.801.201.602.00（1）实验中电压表应选用B；电流表应选用E；滑动变阻器应选用F．  （请填写选项前对应的字母）．（2）不改动已连接导线，在实物连接图（a）中把还需要连接的导线补上．闭合开关前，应使滑动变阻器的滑片放在最左（选填“左”或“右”）端．（3）在图（b）中画出小灯泡的U-I曲线．