如图所示,矩形线框的质量m=0.016kg,长L=0.5m,宽d=0.1m,电阻R=0.

如图所示,矩形线框的质量m=0.016kg,长L=0.5m,宽d=0.1m,电阻R=0.1Ω.从离磁场区域高h1=5m处自由下落,刚入匀强磁场时,由于磁场力作用,线框正好作匀速运动.

    (1)求磁场的磁感应强度;

    (2) 如果线框下边通过磁场所经历的时间为△t=0.15s,求磁场区域的高度h2.

答案


解析:

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