单选题以下对电磁波的认识，正确的是（ ）．A电冰箱是利用电磁波工作的B可见光不属于电磁波C电磁波可以用来传播信息D电磁波在真空中的传播速度是3.0×105 m／s
单选题
以下对电磁波的认识，正确的是（ ）．
A
电冰箱是利用电磁波工作的
B
可见光不属于电磁波
C
电磁波可以用来传播信息
D
电磁波在真空中的传播速度是3.0×105 m／s
参考解析
解析：
AB两项，电冰箱是利用物态变化时的吸热和放热原理制冷的，不是利用的电磁波，可见光属于电磁波；C项，电磁波可以用来传播信息，现代通信主要应用的是电磁波；D项，电磁波在真空中的传播速度为3.0×108m／s．
AB两项，电冰箱是利用物态变化时的吸热和放热原理制冷的，不是利用的电磁波，可见光属于电磁波；C项，电磁波可以用来传播信息，现代通信主要应用的是电磁波；D项，电磁波在真空中的传播速度为3.0×108m／s．
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