How Hot Does a Flashlight Bulb Get When Turned On?

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A common flashlight bulb operates at 0.200 A and 3.80 V, leading to a calculated resistance of 19 ohms when on. The initial resistance of the tungsten filament at 20°C is 1.10 ohms, indicating a significant increase in resistance when heated. To estimate the filament's temperature, the temperature coefficient for tungsten, 0.0045, is essential for determining how resistance changes with temperature. The discussion emphasizes the need for accurate calculations to avoid approximations, as only one attempt remains to solve the problem. Understanding the relationship between resistance and temperature is crucial for finding the filament's operating temperature.
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A common flashlight bulb is rated at 0.200 A and 3.80 V (the values of current and voltage under operating conditions). If the resistance of the bulb's tungsten filament at room temperature (20.0°C) is 1.10 , estimate the temperature of the tungsten filament when the bulb is turned on.
 
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Please make an attempt to solve the problem and maybe someone will help.
 


Well... what I've tried to do was find the resistance which is R=E/I and I got 3.8/.2 = 19... then I divided that by 1.10 and got 17.27... someone told me to look up in a tungsten chart the value of the new temperature but the chart gives approximations. I've tried 3 attempts, I have 1 left so I can't make anymore approximations... I was wondering if anyone knew a way to find the correct temperature
 

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