Power Dissipation in 70W/240V Globe

AI Thread Summary
To determine the actual power dissipated by a 70W, 240V globe connected to a cord with two 0.6 ohm wires, first calculate the bulb's resistance using its rated values. The total circuit resistance includes the bulb's resistance and the resistance of the cord. By applying Ohm's law, the total current can be calculated, which is then used to find the actual power output of the bulb. The rated wattage is not a fixed value, and actual power dissipation may vary based on circuit conditions. Understanding these principles is essential for accurate power calculations in electrical circuits.
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If you have a globe marked 70W and 240V and you connect it to one end of cord( which has two wires, each of 0.6 ohms), and the other end of the cord is connected to a 240V outlet, what is actual power dissipated by the globe?
 
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Here are a few pushes in the right direction.

The rating on the bulb (70W at 240 V) does not mean that either wattage or voltage is a "set" constant for the bulb. But from these two values, you can find a property that is constant for the bulb, specifically its resistance (assuming there is not significant difference in temperature between the rated and actual power output).

So, assume a voltge of 240V across the circuit, find the total current through the circuit (using total resistance), then find power output of the bulb.
 
Thanx for that advice, it was very helpful
 

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