Electricity help, calculating the current

AI Thread Summary
To calculate the current in the relay coil connected to a 12 V supply, Ohm's Law (V = IR) is applied. Given the resistance of the relay coil is 150 ohms, the current can be determined using the formula I = V/R, resulting in a current of 0.08 A (or 80 mA). Additionally, the power equation (P = IV) confirms that the relay operates within the specified power rating. The discussion emphasizes the importance of understanding these fundamental electrical principles rather than simply providing answers. Mastery of these concepts is essential for effective problem-solving in electrical applications.
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In a motor vehicle, a relay is used to switch the 12 V , 60 W headlight on and off.


The resistance of the relay coil is 150 ohms . Calculate the current in the relay coil when it is connected to a 12 V supply.
 
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On this site it seems people prefer to encourage independent thought rather than just give the solution, but I'm not sure there's much else to say here. The relations relevant at this level are:

V = IR

P = IV
 
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