Question

The filament of 240V , 100W electric lamp heats up from room temperature to its operating temperature as it heats up its resistance increases by a factor of 16 what is the resistance of this lamp at room temperature?

please explain with solution

Answer 1

is the answer★★★★★...........

Answer 2

Hey buddy,

◆ Answer-
R0 = 36 ohm

◆ Explanation-
# Given-
P = 100 W
V = 240 V
R = 16 R0

# Solution-
At operating temperature, Power of the bulb is calculated by -
P = V^2 / R
R = V^2 / P

Substituting values -
R = 240^2 / 100
R = 576 ohm

Resistance at room temprature is given by-
R0 = R/16
R0 = 576/16
R0 = 36 ohm

Resistance of the lamp at room temperature is 36 ohm.

Hope this helps...