temperature graph question

[Guest sheikhfahad]

I am doing an investigation on to find the relationship between the temperature of the surface of the bulb with its power.

 

Can some 1 tell me how the graph of this relationship would look like thank you

[Cap'n Refsmmat]

Perhaps you should do your investigation and find out yourself...

 

I'd think it would slowly curve up, and get steeper and steeper, because large bulbs are lots less efficient.

[Guest sheikhfahad]

Perhaps you should do your investigation and find out yourself...

 

I'd think it would slowly curve up' date=' and get steeper and steeper, because large bulbs are lots less efficient.[/quote']

to be honest i cant find anything, but i think it going to be:

 

As power equals P=V^2/R,

We know R is proptional to T

so as power increase R must decrease so will T decrease.

 

Is that right or am i chatting crap?

 

thank u

[Dave]

(moved to General Science because it's a better home for the thread)

[BPHgravity]

A better formula to use would be P=I^2xR. When voltage is constant, resistance must be reduced for current to increase. As resistance is lowered, current and power goes up, and so will temperature. So your relationship statment of as R goes down so will T is not correct. I would just do a simple power to temperature graph, using 25-watt, 40-watt, 60-watt, 75-watt, and 100-watt lamps. I would range the temperature from 100 degrees F. to upwards of 500 degrees F with 50 degree intervals.

 

Lamp position must be kept constant for all samples as the surface temperature of the bulb changes with change in orientation of the lamp. The best test position would be bulb up and base down. You will receive maximum temperatures this way at the glass. I would start my plotting a five minutes on time for each lamp. Good Luck.