I've recently just learned from the Internet that a resistor reduce current. But when I measured the amps from the power supple to the resistor in series and then measured again from resistor to an LED. I did not see any amperage dropped, only voltage. Sorry if this is a silly question.

  • \$\begingroup\$ The internet is a tricky place. Since your resistor and led form a series circuit. The current in must be the current out. \$\endgroup\$ – StainlessSteelRat Apr 9 '17 at 23:45
  • \$\begingroup\$ @StainlessSteelRat sorry I don't really understand.. my multimeter is measured between the power supply to the resistor and from the resistor to the LED. The circuit was not connected \$\endgroup\$ – user142208 Apr 9 '17 at 23:48
  • \$\begingroup\$ Was the LED ON? \$\endgroup\$ – StainlessSteelRat Apr 9 '17 at 23:50
  • \$\begingroup\$ @StainlessSteelRat it was not on when powered, I connected the multimeter from one end of the power supple to the resistor(it was on showing the amount of amp) and then measured once more from resistor to LED . Then the led lit up \$\endgroup\$ – user142208 Apr 9 '17 at 23:53
  • 2
    \$\begingroup\$ "A resistor reduces current" means the current goes down after you put the resistor in the circuit. It doesn't mean the current goes down after the current goes through the resistor. \$\endgroup\$ – user253751 Apr 10 '17 at 2:16

The resistor decreases the current in the circuit as a whole.

The current is the same everywhere in a simple looping circuit. If you add more resistance that current reduces.


simulate this circuit – Schematic created using CircuitLab


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