R1和R为两个串联电阻,已知R1=2R2,且R2上消耗的功率为1W,则R1上消耗的功率为()A、2WB、0.25WC、4WD、0.5W
R1和R
- A、2W
- B、0.25W
- C、4W
- D、0.5W
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