盈彩
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FAN-1演示风扇
直流可调速三叶风扇,风叶上▲标有A、B、C字母，用于频闪现象演示。借助频闪仪可看到风叶静止，缓慢顺转、逆转；转叶重叠，转叶换位、转叶数变为3、6、9、12等特有的物理光学效果。
