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微波炉正常工作时托盘的转速为7.5r/min，则该托盘转动的角速度ω为______rad/s，若微波炉中磁控管发射频率为2450MHz的电磁波，则该电磁波的波长为______m．

答案

由ω=2πn，得角速度为ω=2×3.14×

7.5
60
rad/s=0.785rad/s

由=λf，得，电磁波的波长为 λ=

c
f
=
3×108
2450×106
m=0.122m

故答案为：0.785，0.122

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润肠汤功效与作用
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