問題詳情
20.如图所示,位于一水平面内的、两根平行的光滑金属导轨,处在匀强磁场中,磁场方向垂直于导轨所在的平面,导轨的一端与一电阻相连;具有一定质量的金属杆ab放在导轨上并与导轨垂直。现用一平行于导轨的恒力F拉杆ab,使它由静止开始向右运动。杆和导轨的电阻、感应电流产生的磁场均可不计。用E表示回路中的感应电动势,i表示回路中的感应电流,在i随时间增大的过程中,电阻消耗的功率等于
(A)F的功率
(B)安培力的功率的绝对值
(C)F与安培力的合力的功率
(D)iE
(A)F的功率
(B)安培力的功率的绝对值
(C)F与安培力的合力的功率
(D)iE
參考答案
答案:B,D
難度:適中0.5
統計:A(0),B(0),C(0),D(0),E(0) #
個人:尚未作答書單:Practice
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