為了描繪標有“3V，0.4W”的小燈泡的伏安特*曲線，要求小燈*兩端電                    ...

問題詳情：

為了描繪標有“3V，0.4W”的小燈泡的伏安特*曲線，要求小燈*兩端電                              

壓能從零開始變化．所給器材如下：                                                                             

A．電流表（0～200mA，內阻0.5Ω）                                                                            

B．電流表（0～0.6A，內阻0.01Ω）                                                                              

C．電壓表（0～3V，內阻5kΩ）                                                                                   

D．電壓表（0～15V，內阻50kΩ）                                                                               

E．滑動變阻器（0～10Ω，0.5A）                                                                                 

F．電源（3V）                                                                                                              

G．電鍵一個，導線若干．                                                                                            

（1）實驗中所用電流表和電壓表應選用                                                                 

（2）在方框中畫出實驗電路圖1．                                                                                

（3）考慮到金屬電阻率與溫度的關係，圖2中能較正確反映通過小燈泡的電流I與燈泡兩端的電壓U之間的變化關係的是                                                                                                       ．                     

【回答】

（1）AC

（2）如圖

（3）A

知識點：專題十三 中學物理實驗

題型：實驗,探究題