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题目:一定值电阻 R 两端的电压从15伏增加到20伏,通过电阻 R 的电流增加了0.5安,那么电阻 R 的消耗功率增加了__瓦.错解一:△P=AU×AI=5伏×0.5安=2.5瓦错解二:△P=P_2-P_1=(U_2~2/R)-(U_1~2/R)=(△I)~2·R
Title: The voltage across the resistor R increases from 15 volts to 20 volts, and the current through the resistor R increases by 0.5 amps. The power consumption of the resistor R increases by __watt. The wrong solution is: △P=AU×AI= 5 volts × 0.5 ampere = 2.5 watts wrong solution II: △P=P_2-P_1=(U_2~2/R)-(U_1~2/R)=(△I)~2·R