How Do You Calculate Current in Lamps with Different Wattages?

AI Thread Summary
To calculate the current through lamps with different wattages, the formula I = P/V is used, where I is current, P is power in watts, and V is voltage. For a 60W lamp at 120V, the current is 0.5A, and for a 120W lamp at 120V, the current is 1A. The calculations were confirmed as correct, emphasizing the importance of matching units to avoid errors. This method effectively determines the current for lamps with varying wattages. Understanding these calculations is essential for electrical applications.
Elliott.98
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A 60W lamp and a 120W lamp each have a potential difference of 120V across their terminals.

a) What is the current through each lamp?

I think you use the formula I = P/V and so:

Lamp #1 = I = 60/120 and Lamp #2 = I = 120/120

But I don't know if that is right?

Thank you so much for the help!
 
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Elliott.98 said:
But I don't know if that is right?

It's absolutely correct.

( Generally: Remember units. If they don't match, you have made an error ).
 
Hesch said:
It's absolutely correct.

( Generally: Remember units. If they don't match, you have made an error ).

Ok, thank you!
 

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