Resistance of the element,
Resistance of heating element at room temperature,
Temperature coeffient of the material of resistor,=1.70 x 10–4°C–1
Now, using the relation
is the required temperature of the element.
EMF of battery,
Internal resistance of battery, r=
Current flowing in the circuit, I= 0.5 A
Using the forlmula
where, R is the external resistance.
is the required resistance.