试题与答案

(8分)如图所示,在同一水平面的两导轨相互平行,相距2 m并处于竖直向上的匀强磁

题型:计算题

题目:

(8分)如图所示,在同一水平面的两导轨相互平行,相距2 m并处于竖直向上的匀强磁场中,一根质量为3.6 kg的金属棒放在导轨上,与导轨垂直.当金属棒中的电流为5 A时,金属棒做匀速直线运动,当金属棒中的电流增加到8A时,金属棒将获得2m/s2的加速度(g取10m/s2) 求:

(1)磁场的磁感应强度;

(2)导轨与金属棒间动摩擦因数.

答案:

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