Question

How long would it take a current of 10 amperes to put a layer of copper 0.1 mm thick on both sides of a rectangular plate of 10 cm x 1 x 65 cm (e.c.e. of copper = 0 x 00033 gm/coul, density of Copper = 9 gin/cc)?

• A. 9 sec
• B. 9 min
• C. 450 sec
• D. 900 min

Answer 1

The correct option is C 450 sec

Mass of copper deposited $=Volume\times Density$

$=10\times 1.65\times \frac{0.1}{10}\times 9$ gm

Time taken for deposition, $t=\frac{m}{zi}$

$=\frac{10\times 1.65\times 0.1\times 9}{10\times 0.00033\times 10}$sec

$=450$ sec