Appliance 82079

The voltage at the terminals of the appliance is 4.5 V. A current of 0.5A passes through the appliance. What voltage must the appliance have if a current of 0.7A is to pass through it?

Correct answer:

U₂ =  6.3 V

Step-by-step explanation:

$$\begin{gathered} U_1=4.5\text{V} \\ {I}_1=0.5\text{A} \\ {I}_2=0.7\text{A} \\ U=R\cdot I \\ R=U_1/I_1=4.5/0.5=9\Omega \\ {U}_2=R\cdot I_2=9\cdot 0.7=6.3\text{V} \end{gathered}$$

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