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Question
If the reading of the ammeter, A1 in the following figure is 2.4 A, what will be the readings of ammeters A2 and A3? Neglect the resistances of the ammeters.
Solution
Given: i1 = 2.4 A
Since the 20 Ω and 30 Ω resistors are connected in parallel, the voltage across them will be the same.
From the figure,
\[20 i_1 = 30\left( i - i_1 \right)\]
\[ \Rightarrow 50 i_1 = 30i\]
\[ \Rightarrow i = \frac{50 i_1}{30} = 3 . 99 = 4 A\]
∴ The reading of ammeter A3 = i = 4 A
The reading of ammeter A2 = i - i1 = 1.6 A
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