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# Amperes

Im kind of interested in messing with some basic electronics (which i know very little about) and my question is if I have 2 dc devices that have a 900ma draw on both like 2 cell phones .... do I need 2 separate circuits that can handle the individual loads or do i need 1 circuit that outputs say 2a they both take what they need from?

## Discussions

5 years ago

You are perfectly correct: 1 circuit outputting 2amps will feed the 2 cell phones (0.9 amps each).

This can be explained using Ohms Law: I =V/R. The Current (I) will equal the Voltage (V) divided by the Resistance (R). V and R will be constant, as your power source (V) will be stable and the resistance (R) of each phone will be the same (I assume). Make sure that you use the correct voltage supply to ensure the correct current though. Here in the UK its 230V AC.

Keep messing around!

Reply 5 years ago

sorry, you said DC and I said AC. However, same principle applies.

Reply 5 years ago

Also, I'm assuming that you are connecting the loads in PARALLEL to the voltage source (like domestic loads), not SERIES. The voltage across each load will therefore stay the same and the current will be 0.9amps per load (if you connect in series the voltage across each load will half and the current will half too).

Hope that makes sense