Question
The resistance of the rheostat shown in the figure. is $30\Omega.$ Neglecting the meter resistance, find the minimum and maximum currents through the ammeter as the rheostat is varied.
✓
Answer
$\text{i}_\text{min}=\frac{5.5\times3}{110}=0.15$
$\text{i}_\text{min}=\frac{5.5\times3}{20}=\frac{16.5}{20}=0.825.$
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