When the tungsten filament in a 60 W, 120 V light bulb reaches 1970° C, 60 W of

Question

When the tungsten filament in a 60 W, 120 V light bulb reaches 1970° C, 60 W of electric power is used to produce light and heat.

(a) Find the current through the filament under these conditions, which are established very shortly after the light is turned on. Correct: My answer was .5A

(b) Find the filament current when the light is first turned on, assuming an initial filament temperature of 20° C. Correct: My answer was 4.985 A

-Find the power used when the light is first turned on, assuming an initial filament temperature of 20° C. Correct: My answer was 598.2 W

(c) Estimate the time needed to heat the filament to 1970° C. The filament has a mass of 0.041 g and a specific heat of 0.032 cal/g-C°. My answer was incorrect multiple times. Im going to give you as much information on this one as I can because I keep getting it wrong. I've looked on chegg Q&A and the comments for part C for this question say the answer to it is wrong everytime. The people mostly work the problem the same way every single time. What I've been doing is plugging my numbers in with the constants given and I get it incorrect.

My answers so far have been

.0179 s

17.9 s

.017 s

.018 s

.178 s

.17 s

.107s

.16 s

and .1 s

The way I first calculated the problem was (.000041*133.95*1950)/598.2=.179 s orignally

Please help me on this one. Ive been working on this one for 45 minutes and can't get it.

Explanation / Answer

try 0.0615 sec

if thats correct ask for solution in comment below if u need.

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