Tiaotiao Learn

High school physics · IGCSE · A-level · AP · IB

Free physics lessons that start with a question.

Most problems look hard because we haven't found the one idea inside them. We look for it together.

Start with KinematicsHow Tiaotiao learns

Video lessons and printable study sheets by Tiaotiao (跳跳学长), a Peking University graduate. The videos have English audio and subtitles. Everything is free. You don't need an account or an email address.

读得懂中文？每一讲都有中文学习单。看中文页 →

Lesson 8 · Change in velocity

Question

A ball hits the ground at 5 m/s and bounces up at 2 m/s. What is Δv?

The simple version

Down is +, so v₀ = +5 and vₜ = −2. Δv = −2 − 5 = −7 m/s, up.

A mistake I made

I did 5 − 2 = 3.

A sample notebook entry from Lesson 8. How Tiaotiao learns →
  • 10Kinematics lessons
  • 12exam syllabuses checked. Find yours →
  • Freestudy sheets, no sign-up
“There is no shortcut. Not one of the strong students I knew, in high school or at Peking University, got good grades without putting in a lot of time.”— Tiaotiao

How it works

  1. Watch the lesson. It is taught in Mandarin. On YouTube you can choose English audio or English subtitles.
  2. Download the study sheet. It's a free PDF with the key ideas, in English or Chinese.
  3. Try the practice questions. Then check your work against the answers.

Physics · Kinematics (Motion)

More units are coming.

  1. 1Point Mass (Particle) Explained
  2. 2Frame of Reference & Coordinate System
  3. 3Instant vs Time Interval
  4. 4Scalars vs Vectors
  5. 5Distance vs Displacement
  6. 6Average Speed vs Average Velocity vs Instantaneous Velocity
  7. 7How to Find Average Velocity of a Multi-Part Trip
  8. 8How to Find Change in Velocity: Why It's 7, Not 3
  9. 9What Is Acceleration? Why It's 180, Not 20
  10. 10Speeding Up or Slowing Down? Check a and v

These lessons cover topics from Cambridge and Edexcel IGCSE, AQA GCSE, A-level (Cambridge, AQA, OCR and Edexcel), AP Physics 1, IB, CBSE Class 11, NSW HSC and Ontario SPH3U. No single syllabus includes all 10 lessons. Check your syllabus →

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Meet Tiaotiao

Tiaotiao graduated from Peking University and teaches high school physics on YouTube. In China, students know Tiaotiao as 跳跳学长.

More about Tiaotiao →