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A brass plate having surface area 200 cm...

A brass plate having surface area `200 cm^2` on one side is electroplated with `0.10 mm` thick silver layers on both sides using a `15 A` current. Find the time taken to do the job. The specific gravity of silver is `10.5 ` and its atomic weight is `107.9 g mol^(-1)`

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The correct Answer is:
B, D
`i=15 A`
` surface area =200 cm^2`
` Thickness = 0.1 mm volume of Ag deposited `
`= 200 xx0.01 cm^3 = 2 cm ^3 for one side. `
`rArr 42 = Z_(Ag) xx 15 xx T`
` rArr T = (42xx96500)/(107.9 xx 15)`
`=2504.17 see ~~42 min`
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