The output

The output voltage of the transformer is 880 V. The secondary coil has 1200 turns. Transformation ratio k = 4. Find the voltage to which the primary coil is connected. How many turns does the primary coil have if a current of 1 A flows through it? What current flows through the secondary coil?

Correct answer:

U₁ =  220 V
n₁ =  300
I₂ =  0.25 A

Step-by-step explanation:

$$\begin{gathered} U_2=880\text{V} \\ {n}_2=1200 \\ {I}_1=1\text{A} \\ k=4 \\ k=U_2/U_1 \\ {U}_1=U_2/k=880/4=220\text{V} \end{gathered}$$

$$\begin{gathered} k=n_2/n_1 \\ {n}_1=n_2/k=1200/4=300 \end{gathered}$$

$$\begin{gathered} P=I_1\cdot U_1=1\cdot 220=220\text{W} \\ P=I_2\cdot U_2 \\ {I}_2=P/U_2=220/880=0.25\text{A} \end{gathered}$$

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