Calculating Tungsten Melting Temperature Using Circuit and Ohm's Law

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Homework Help Overview

The original poster is exploring a method to calculate the melting temperature of tungsten using a circuit with a tungsten filament lamp and Ohm's Law. They have provided specific parameters such as the voltage and known values for resistivity and temperature coefficient.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster suggests increasing the voltage until the lamp turns off to measure current and calculate resistance, which they believe could then be used to find the corresponding temperature. Some participants question the validity of this approach and the definitions of the terms used.

Discussion Status

The discussion includes a mix of attempts to clarify the original poster's reasoning and the feasibility of their proposed method. There is no explicit consensus, but some guidance is being offered regarding the assumptions made in the original reasoning.

Contextual Notes

The original poster expresses urgency in finding a solution, which may influence the pace and nature of the discussion. There is an acknowledgment of potential misunderstandings in the approach taken.

Gyroscope

Homework Statement



[tex]p_t=p_{20}(1+\alpha (t-20))[/tex]

I have a circuit with a 3,5 V lamp that has a tungsten filament. I can provide to the circuit a variable voltage. How would I find the melting temperature of tungsten?

I know p_20 and alpha and the voltage I provide. And I have an device to measure current too.

Could I just increase voltage until the lamp turns off (which means the tungsten filament melted), measure the current and by means of Ohm's Law I could find the resistance. And then with the initial formula, I could find the temperature to which corresponds this resistance.

Am i right? Sorry my poor English.
 
Last edited by a moderator:
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knock, knock...

Sorry to reply to my own thread, but I have some urgence to solve this, please, please...
 
If you're expecting to have homework problems solved for you within 2 hours, then you're probably at the wrong place.

What happens if you follow up on your original reasoning? Also how are your terms defined?
 
You are totally right. I am sorry...
 

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