A three-way lightbulb has two filaments with resistances R1 and R2 connected in

Question

A three-way lightbulb has two filaments with resistances R1 and R2 connected in series. The resistors are connected to three terminals, as indicated in the figure (Figure 1) , and the light switch determines which two of the three terminals are connected to a potential difference of 120V at any given time. When terminals A and B are connectedto 120V the bulb uses 80 W of power. When terminals A and C are connected to 120V the bulb uses 40 W of power.

What is the Resistance R1? _______(ohms)

What is the resistance R2?_________(ohms)

How much power does the bulb use when 120V is connected to terminalsBand C? ____________=W

Explanation / Answer

R1 = 120^2/80 = 180 ohms R1+R2 = 120^2/40 = 360 ohms thus R2 = 180 ohms power = 80 watts

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.