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Ohm's Law Calculator

Run the Ohm's Law Calculator MicroSim Fullscreen

About This MicroSim

An interactive Ohm's Law triangle with three circles labeled V (volts), I (current), R (resistance). Two inputs are active at a time; the third is calculated.

Learning objective: Applying - the student can solve Ohm's Law problems for any unknown variable.

How to Use

Use the on-screen controls - buttons, sliders, dropdowns, and clickable regions - to explore the idea. Every change updates the canvas immediately, so you can predict an outcome and then check it.

Iframe Embed Code

You can place this MicroSim on any web page by adding the following HTML:

<iframe src="https://dmccreary.github.io/moving-rainbow/sims/ohms-law-calculator/main.html"
        height="362px"
        width="100%"
        scrolling="no"></iframe>

Lesson Plan

Grade Level

Grades 6-12

Duration

10-15 minutes

Learning Objective

Applying - the student can solve Ohm's Law problems for any unknown variable.

Activities

  1. Explore (5 min): Open the MicroSim and try every control. Notice what changes on screen.
  2. Predict (5 min): Before each change, predict what will happen, then test your prediction.
  3. Discuss (5 min): Explain the idea in your own words and connect it to the LED code in Chapter 15.

Assessment

Ask students to describe, in one or two sentences, the relationship the MicroSim demonstrates and how it shows up when programming the LED strip.

References

  1. Chapter 15: Electronics Fundamentals — Resistance, Ohm's Law, and Components - the chapter where this MicroSim is used.
  2. Moving Rainbow Intelligent Textbook - the full course this MicroSim belongs to.
  3. MicroSims Reference - the standards behind these interactive simulations.

Original Specification

Full specification used to generate this MicroSim 
Type: interactive-infographic
**sim-id:** ohms-law-calculator
**Library:** p5.js
**Status:** Specified

An interactive Ohm's Law triangle with three circles labeled V (volts), I (current), R (resistance). Two inputs are active at a time; the third is calculated. A dropdown lets the user choose which value to solve for. Numeric input fields accept values. Below the triangle, the formula is displayed with the current values substituted: e.g., "I = V ÷ R = 5 ÷ 220 = 0.023 A = 23 mA". A second section shows the power formula: "P = V × I = 5 × 0.023 = 0.115 W". Clicking any circle highlights the formula. Canvas: 700 × 350 px. Responds to window resize.

Learning objective: Applying — the student can solve Ohm's Law problems for any unknown variable.