Physics · Unit 1: Kinematics ·  Project 1-1-4

Motion Detector Graph Match

🚀 PROJECT

You get a target position-time graph. Your job: walk in front of the sensor and reproduce it exactly. Simple to explain, surprisingly hard to do — and that gap is the whole point  ·  3 class days

Synthesizing1-1-1 · distance & displacement1-1-2 · reading x(t) graphs1-1-3 · signed velocity
Unit 1: Kinematics

🧭 Project Summary

A motion detector sits at one end of a track and pings position over time, plotting it live as a position-time graph. Your teacher will hand you a target graph — a specific shape made of straight segments — and your job is to walk in front of the sensor so that your own live graph matches it as closely as possible.

Here's the catch: knowing what the graph should look like and actually producing it with your body are two very different skills. You can't instantly jump from standing still to 2 m/s, you can't turn on a dime at a sharp corner, and a half-second of hesitation shows up on the graph as clearly as a shout. This project is where "I understand graphs" turns into "I can perform one."

The three days

1Study your target graph and build a walking strategy — no sensor yet.
2Live attempts with the motion detector. Print and compare each try, then revise your plan.
3Final graded attempt. Print your best match and write up your strategy.

Turn in

  • Your best matched graph printout, alongside the original target graph
  • A written explanation of your strategy — segment by segment, in the vocabulary of distance, displacement, speed, and signed velocity

Why it matters

Everything from the first two weeks of Unit 1 shows up here at once: you have to read a graph (1-1-2), translate its slopes into speeds and directions using a sign convention (1-1-3), and describe what actually happened using precise vocabulary (1-1-1) when your walk doesn't match perfectly — which, the first time, it almost never does.

🧩 Before You Start — Prerequisite Check

This project assumes you're solid on Lessons 1-1-1 through 1-1-3. Check yourself honestly — if something's shaky, the review links in the sidebar are exactly what they're there for.