Electrochemical machining is performed to remove material

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Electrochemical machining is performed to remove material from an iron surface of 20 mm × 20 mm under the following conditions:
Inter electrode gap = 0.2 mm
Supply voltage (DC) = 12 V
Specific resistance of electrolyte = 2 ohm- cm
Atomic weight of iron = 55.85
Valency of Iron = 2
Faraday's constant = 96540 Coulombs
The material removal rate (in g/s) is

1. 0.3471
2. 3.471
3. 34.71
4. 347.1

Correct Option: A

We know, R =	ρl
	A

where, ρ = resistivity
= special resistance of electrolyte
= 2Ω
R =resistance of electrolyte between electrodes
l = interelectrode gap = 0.2mm
A = electrodes cross-sectional area = 20 × 20 mm²

∴ R = (2 × 10) ×	0.2	= 0.01Ω
	20 × 20

∴ Current, I =	V	=	12	= 1200 A
	R		0.01

Faraday of electricity, E =	M
	v

where, E = equivalent weight
M = molecular weight
v = valency

M.R.R (gm/sec) =	I	×	M
	F		v

=	1200	×	55.85	= 0.3471
	96540		2