Question

A 2-way light bulb for a 110. V lamp has filament that uses power at a rate of 50.0 W and another filament that uses power at a rate of 100. W. Find the resistance of these two filaments.

Answer 1

Given:

The potential difference is,

`V=110\text{ V}`

The power of the first filament is,

`P_1=50.0\text{ W}`

The power of the second filament is,

`P_2=100\text{ W}`

To find:

resistance of these two filaments

Step-by-step explanation:

The power of the filament is,

`P=(V^2)/(R)`

The resistance of the first filament is,

`\begin{gathered} R_1=(V^2)/(P) \\ =(110*110)/(50.0) \\ =242\text{ ohm} \end{gathered}`

The resistance of the second filament is,

`\begin{gathered} R_2=(110*110)/(100) \\ =121\text{ ohm} \end{gathered}`

Hence, the resistances of the filaments are 242 ohms and 121 ohms.