问题
填空题
实验告诉我们，______的电流能够产生电磁波；电磁波在______中传播速度最快，是______m/s．
答案
迅速变化的电流周围产生电磁波，且电磁波在真空中的传播速度和光速相等，都是3×108m/s．
故答案为：迅速变化；真空；3×108．
搜题请搜索小程序“爱下问搜题”
实验告诉我们，______的电流能够产生电磁波；电磁波在______中传播速度最快，是______m/s．
迅速变化的电流周围产生电磁波，且电磁波在真空中的传播速度和光速相等，都是3×108m/s．
故答案为：迅速变化；真空；3×108．
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