Question Part Points Submissions Used Question Part Points Submissions Used Ques

Question

Question Part Points Submissions Used Question Part Points Submissions Used Question Part Points Submissions Used Question Part Points Submissions Used Question Part Points Submissions Used (a) What is the hot resistance (in ) of a 23 W light bulb that runs on 120 V AC? (b) If the bulb's operating temperature is 2700 °C, what is its resistance (in ) at 2540 °C? __________ (b) If the bulb's operating temperature is 2700 °C, what is its resistance (in ) at 2540 °C? __________ If the bulb's operating temperature is 2700 °C, what is its resistance (in ) at 2540 °C? __________ Question Part Points Submissions Used k -XX"x-)x-**)#7 EI *

Explanation / Answer

P =23 W, V = 120 V

(a) P = V^2/R

23 = 120^2/R

R = 626.1 ohms

(b) Temperature coefficient of tungsten alpha = 0.004403 /oC

R2 = R1(1+alpha(T2 -T1)

R2 = 626.1 (1+0.004403(2540-2700))

R2 = 185 ohms

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

---