arc flash energy question
arc flash energy question
(OP)
1 cal/cm2 equals ~4 joules. So does that mean an 8 cal incident energy equals the effect of a 32 cal incandescent light bulb? Doesn't seem like much heat.
When was the last time you drove down the highway without seeing a commercial truck hauling goods?
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arc flash energy question
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RE: arc flash energy question
RE: arc flash energy question
RE: arc flash energy question
RE: arc flash energy question
Keith Cress
kcress - http://www.flaminsystems.com
RE: arc flash energy question
RE: arc flash energy question
An arc flash can reach tempatures up to 36,000 degrees F, that about 20 time the tempature necessary to melt steel or about 5 times as hot as the surface of the sun.
RE: arc flash energy question
That means the sun's power output is 4*10^22 W.
RE: arc flash energy question
Keith Cress
kcress - http://www.flaminsystems.com
RE: arc flash energy question
I guess my point was that sunlight seems pretty bright, but it's only 0.14W/cm^2. The OP was commenting that 32W/cm^2 didn't seem like very much. Seems like more when you consider it's 230x stronger than sunlight.
RE: arc flash energy question
RE: arc flash energy question
RE: arc flash energy question
Mathcad's 15 degree calorie cal15 equals 4.186 J. Mathcad's 20 degree calorie cal20 equals 4.182 J. Mathcad's Dietetic Calorie dcal equals 4186 J. Mathcad's kilocalorie kcal equals 4186 J. Mathcad's mean calorie mcal equals 4.19 J. Mathcad's Thermochemical Calorie tcal equals 4.184 J.
RE: arc flash energy question
RE: arc flash energy question
RE: arc flash energy question
RE: arc flash energy question
RE: arc flash energy question
My soldering iron is 25W, but the tip probably emits 10W of heat, the rest being lost elsewhere. Now- hold the tip- probably 0.5cm2- on your face for 0.25 seconds and see how it feels. Tell me when the blister finally heals.
BTW, a dietary calorie is actually a kilocalorie- so why don't I spontaneously ignite when I eat this 75 (k)calorie cookie?