The resistance of an ammeter is 13 Ω and its scale is

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The resistance of an ammeter is 13 Ω and its scale is graduated for a current upto 100 amps. After an additional shunt has been connected to this ammeter it becomes possible to measure currents upto 750 amperes by this meter. The value of shunt-resistance is

1. 2 Ω
2. 0.2 Ω
3. 2 k Ω
4. 20 Ω

Correct Option: A

We know

	I	= 1 +	G
	I_S		S

	750	= 1 +	13
	100		S

S ⇒ 2Ω