题目

People tend to become more personal and hide less of themselves when using email. Some Britain researchers have found in a recent study that there are good reasons for this. The team of researchers asked 83 pairs of students, all strangers to each other, to solve a problem. They had to discuss this question: ___36.___ The pairs of students had to talk over the problem either face to face or by computers. Dr. Johnson said, “They told their partners four times as much about themselves when they talked over the Internet as when they talked face to face. When the computers were fitted 6.如图1所示是“探究通过导体的电流与电压、电阻关系”的电路图.所用实验器材是:电源(6V)、电流表(0~0.6A)、电压表(0~3V)、电阻箱(0~999.9Ω)、滑动变阻器(40Ω 2A)、开关、导线若干.表一:序号电压U/V电流I/A11.00.2021.50.3032.00.40表二:序号电阻R/Ω电流I/A150.402100.203200.10(1)探究电流与电压的关系时,所测得的几组电流、电压值见表一.分析表中数据可知:电阻箱接入电路的阻值为5Ω;当导体的电阻一定时,通过导体的电流与导体两端的电压成正比关系.(2)探究电流与电阻的关系时,应调节电阻箱,改变接入电路中的阻值,并调节滑动变阻器使电压表的示数保持相同,读出电流值,所测得几组数据见表二.分析表中数据可知:电阻箱两端的电压为2V;当导体两端电压一定时,通过导体的电流与导体的电阻成反比关系.(3)请根据表一中数据在图2中画出电阻R的U-I关系图象.(4)在许多实验中都需要进行多次测量,其目的有以下两种:A.是为了从不同情况中找到普遍规律;B.是为了求平均值以减小误差.你认为在本实验中测量多组数据的目的是A;“伏安法”测量定值电阻的阻值实验中多次测量的目的是B(选填“A”或“B”).
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