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扬声器和耳机的构造和原理

> 人们根据物理原理或规律制造出许多机器设备，下列叙述中正确的是 A.投影仪是利用平面镜成像的原理 B.发电机是利用电磁感应现象制成的 C.内燃机是将机械能转化为内能的机器 D.发电机是将电能转化成机械能的机器

问题：

发布时间：2024-09-08

人们根据物理原理或规律制造出许多机器设备，下列叙述中正确的是

A.投影仪是利用平面镜成像的原理
B.发电机是利用电磁感应现象制成的
C.内燃机是将机械能转化为内能的机器
D.发电机是将电能转化成机械能的机器

参考答案：

提问用户：2N***b6u

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