I could really use some help on this question--a detailed explanation please! I

Question

I could really use some help on this question--a detailed explanation please! I attempted to use the formula, time = (specific heat * mass* change in temp) divided by Power and keep getting the wrong answer....For Power I used 60 W and for change in temp I used 1970 Celsius.

When the tungsten filament in a 60 W, 120 V light bulb reaches 1990° C, 60 W of electric power is used to produce light and heat. Estimate the time needed to heat the filament to 1990° C. The filament has a mass of 0.041 g and a specific heat of 0.032 cal/g-C°. *The initial filament temperature was given as 20 Celsius

Explanation / Answer

Initial Temp = 20 ° C
Final Temp = 1990 ° C

Specific Heat, S = 0.032 cal/g-C
Mass, m = 0.041 g

Heat added in raising temperature, q = m*S *T
q = 0.041 * 0.032 * (1990 - 20) cal
q = 2.58 cal
q = 10.8 J

Now,
Power = q/t
t = q/Power
t = 10.8/60
t = 0.18 s

Time needed to heat the filament, t = 0.18 s

p.s - Maybe you were not converting Calories to Joules & getting the wrong answer, rest your logic is right.

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