jc456
Diamond Member
- Dec 18, 2013
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yep no cold flow to the sensor, just like we said. so still waiting on you jethro.yes, so?Funny, but you need to reread ityep, it's a good link, you should read better on the two way energy flow as that sentence continues...
"it may be with a positive sign as well as with a negative sign; that is, energy can flow either from an object to the sensor or from the sensor to the object." This is exactly what I'm saying and SSDD, he can chime in here if he's interested..
and then there is this.... I thought all things emit all the time even if at the same temperature, well?
"When both the sensor and the object are at the same temperature, the flux is zero and the output voltage is zero. This carries a message that the temperatures are the same."
When they're discussing flux, they're discussing net flow.
From page 129.....
The Stefan-Boltzmann law specifies the radiant power (flux) that would be emanated from a surface of temperature, T, toward an infinitely cold space (at absolute zero). When thermal radiation is detected by a thermal sensor, the opposite flowing radiation from the sensor toward the object must also be accounted for. A thermal sensor is capable of responding only to a net thermal flux, i.e., flux from the object minus flux from itself toward the object.
Keep trying!!
OK.
A thermal sensor is capable of responding only to a net thermal flux, i.e., flux from the object minus flux from itself toward the object.
"it may be with a positive sign as well as with a negative sign; that is, energy can flow either from an object to the sensor or from the sensor to the object."
Yup. Net to or away.