TS EAMCET 06 May 2019 Shift 1 Solved Paper

A 100 W tungsten light bulb has a resistance of 250 Ω when it as turned ON and 25 Ω when turned OFF. The ambient room temperature is 25 °C. Find the temperature of the filament when the bulb is turned ON : (Let αmagnetism = 4.5 × 10−3/ °C)