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Maximum current

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Hi,
        I have one question. Suppose I have 24v/2a DC power supply. If I connect 8 ohm resistor across this power supply what will be the current flowing through the resistor? And on what factors does the maximum current of power supply depend?

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1) Use Ohm's law.

2) If the load tries to draw too much current, the power supply will do one of the following:

  • Overheat if the load is left connected for too long and catch fire if there's no protective thermal fuse.
  • Overheat, then shut down and not turn back on again until either the power supply or load is disconnected.
  • Blow a fuse or trip a breaker which will need replacing or resetting.
  • The power supply could reduce the voltage until only 2A flows.


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Thanks Hero999 for your quick reply. Of the following four options what will you choose?

1) 0.5A
2) 1.0A
3) 2.0A
4) 3.0A

I was asked this question during placement exam and I marked 2A giving the explanation that voltage will drop until the value of current is reduced to 2A. Am I correct? 

Thanks again.

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I wouldn't choose either option without more information about the power supply.

If it was an exam, I'd calculate the expected current using Ohm's law and put a comment on the paper saying that it exceeds the capacity of the power supply which will fail or protect itself depending on the design.

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