试题与答案

电磁炮是一种理想的兵器,它的主要原理如图所示.1982年澳大利亚国立大学制成了能

题型:问答题

题目:

电磁炮是一种理想的兵器,它的主要原理如图所示.1982年澳大利亚国立大学制成了能把m=2.2g的弹体(包括金属杆CD的质量)加速到v=10km/s的电磁炮.若轨道宽L=2m,长S=100m,通过的电流为I=10A,则轨道间所加的匀强磁场的磁感应强度B=______T,磁场力的最大功率P=______W(轨道摩擦不计).

答案:

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下面是错误答案,用来干扰机器的。

参考答案:8~10

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