P
PromptSchola Prompt-based STEM subjects mastery
Sign In Register for Free
Kinematics · Physics

Relative Motion

Learn how velocities change depending on who is observing — and solve motion problems across moving frames.

This topic includes

Subtopics to master

Build the relative-velocity equation and apply it consistently.

Core idea
Relative Velocity
Express motion of A relative to B with clear vector language.
  • v_AB = v_A - v_B
  • Sign and direction logic
  • 1D and 2D setups
Start subtopic Get the equation right.
Frames
Moving Reference Frames
Translate observations between frames (car/train/river/wind problems).
  • Choosing a reference frame
  • Interpreting given velocities
  • Common real-world scenarios
Start subtopic Perspective changes answers.
Practice
Practice & Exercises
Build speed with classic relative-motion setups (train, river, wind, moving observer).
  • 1D relative velocity drills
  • 2D vector addition problems
  • River-crossing / wind problems
  • Frame selection mini-sets
  • Exam-style word problems
Open practice Turn confusion into clarity.