Ta có:
\(\dfrac{U_1}{U_2}=\dfrac{I_1}{I_2}\Leftrightarrow I_2=\dfrac{I_1.U_2}{U_1}=\dfrac{0,24.2,5}{4}=0,15\left(A\right)\)
3. Ta có:
\(\dfrac{U_1}{U_2}=\dfrac{I_1}{I_2}\Leftrightarrow\dfrac{4,5}{U_1-0,5}=\dfrac{0,36}{I_2}\Leftrightarrow\dfrac{4,5}{4,5-0,5}=\dfrac{0,36}{I_2}\Leftrightarrow I_2=0,32\left(A\right)\)
Đáp án: B