In the circuit shown, the reading of the Ammeter is doubled after the switch is closed. Each resistor has a resistance $ = 1\,\Omega $ and the ideal cell has an $e.m.f. = 10\, V$. Then, the Ammeter has a coil resistance equal to ................ $\Omega$
A$2$
B$1$
C$2.5$
D
None
Medium
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B$1$
b When switch is closed reading of ameter is $2 \times 5=10 \mathrm{\,A}$
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