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amdx[_3_]

On 6/26/2018 11:06 AM, wrote:
On Tuesday, June 26, 2018 at 11:16:09 AM UTC-4, amdx wrote:
On 6/26/2018 9:37 AM, JBI wrote:
I am getting a platinum coated anode that will have a surface area of 26
cm2 (100 mm long x 8 mm diameter).Â* For my application, the maximum
recommended current density is 200 mA/cm.Â* Based on that, how much
current should be flowing through the anode?Â* I calculate square root of
26 (5.1) times 0.2 which is 1.02 A, is this correct?Â* Thanks.

I'm probably confused but, if it's 8mm in diameter, isn't it 25mm* in
circumference? And, if it's 25mm, then 25mm x 100mm = 2500mm^2,
convert to cm^2 and get 25cm^2. then multiply 200ma x 25cm = 5 amps.
I'll let an adult correct me. I have never seen a platinum coated
electrode.

* have not included areas on end.

Lemme see- surface area of a cylinder = pi x D x H.

3.14159 x 8 = 25.133

25.133 x 100 = 2513.3

0.0200 x 2513.3 = 502.7

Divide by 100 (mm - cm) = 5.02 A.

add the end-cap, if relevant = pi x r^2 = 3.14159 x 16 = 50.27 = 0.01A

Or, close enough.

Peter Wieck
Melrose Park, PA

Sometimes it would be nice for an OP to say, Hey, thanks for the help,
or you're F'ing nuts and don't have clue. Just something, so we know
they didn't get hit by a car!