Temperature-Resistance relationship in a light bulb......?

Question

I know that as temperature increases the resistance of bulb will also increase. I don't know how to estimate the temperature of the filament for a given resistance.

Note: I am looking for a relationship something like R is proportional to T or R is propotional to T^2 or something like that....

Please help!

Answer 1

Here's a nice dissertation of a lab to measure this:

http://phy.asu.edu/phy114-tsen/114%20Physics%20of%20a%20Light%20Bulb.pdf

T/300 = [ R(T)/R(300)]^0.811

In this equation T is the absolute temperature in K, and the room temperature is
assumed to be 300 K. R(T) is the resistance at the temperature T. R(300)
represents the resistance at ambient room temperature.

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Answer 2

You can measure the cold resistance directly with a multi meter. The hot resistance will need to be calculated by measuring voltage and current then using ohms law to determine resistance.

To develop the graph you require will need something to vary the voltage to take different points you can plot on a graph.

Of course if you're lazy like me you can see the results on http://hypertextbook.com/facts/2004/DeannaStewart.shtml

Answer 3

You said it wrong: when a light bulb is turned on, the electrical resistance makes the wire filament heat up. The more resistance, the higher the heat.