A light bulb is rated at 100 W for a 220 V supply. Find (a) the resistance of the bulb. (b) the peak voltage of the source (c ) the rms current through the bulb.

A light bulb is rated at 100 W for a 220 V supply. Find (a) the resist

1.	A light bulb is rated at 100 W for a 220 V supply. Find (a) the resistance of the bulb. (b) the peak voltage of the source (c ) the rms current through the bulb.
Answer» Here, `P = 100 W, E_(v) = 220 V`, `R = ? E_(0) = ? I_(v) = ?` From, `P = (E_(v)^(2))/(R ) , R = (E_(v)^(2))/(R ) = (220 xx 220)/(100) = 484 Omega` `E_(0) = sqrt2 E_(v) = 1.414 xx 220 = 311 V` `I_(v) = (P)/(E_(v)) = (100)/(220) = 0.45 A`

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A light bulb is rated at 100 W for a 220 V supply. Find (a) the resistance of the bulb. (b) the peak voltage of the source (c ) the rms current through the bulb.

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