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Resistor

A resistor limits current and creates voltage drops. Ohm's law says voltage equals current multiplied by resistance.

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Resistance limits current220 Ω ±5%V = I × RV
Concept illustration. Check the component datasheet before wiring.
Try it yourself

Change an input.
See what follows.

A simplified learning model. Values describe the model, not a connected robot.

Working Principle

A resistor limits current and creates voltage drops. Ohm's law says voltage equals current multiplied by resistance.

Step by Step

  1. Higher resistance means less current.
  2. Resistors protect LEDs and sensor inputs.
  3. Series resistors add together.
  4. Parallel resistors lower total resistance.
Resistance limits current220 Ω ±5%V = I × RV
Concept illustration; component appearance and scale are simplified.

Practical learning notes

Key idea

Ohm law is V = I x R. More resistance gives less current for the same voltage.

Use in robot

Resistors protect LEDs, make pull-up/pull-down inputs, and create voltage dividers for signal-level safety.

Safe wiring

Choose resistor power rating when current is high. Small signal resistors are not for motor power.

Classroom check

Calculate LED current with 5V, 2V LED drop, and 220 ohm resistor: about 13.6 mA.

Take the next step

Where this is used

Explore real robotics applications, from mobile robots to inspection and joint motion. Define a measurable target and test one change at a time.

Good ideas start here.

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