Question

The resistance of a tungsten wire used in the filament of a 60w bulb is 240ohms when the bulb is hot at a temperature of 2020 degree what would you estimate its resistance at 20 degree?

Answer 1

Answer:

Explanation:

USE H=I²RT

Where H= Heating effect of electric current. (2020°)

             I= Current flowing in the circuit. ( I )

             R= Resistance (240Ω)

here power is 60 w so use formula P = I²R.

so H = P T.

hope this gives you some hint.

Answer 2

Answer:

Explanation:

The resistance of a tungsten wire used in the fila- ment of a 60w bulb is 2400 when the bulb is hot at a temperature of 2020°C what would you esti- mate its resistance at 20c

[Ans: 25.4]