Topic 4 · Defensive Driving and Safe Driving Practices
What is the 'Three-Second Rule' used for?
- Counting down to a traffic light change
- Determining a safe following distance behind the vehicle in front — correct answer
- Timing your lane changes
Why
It sets your following distance: if you reach a fixed object less than three seconds after the vehicle ahead, you are too close. (Handbook, Section 8.)
Practise this in the real format
Reading one answer is not the same as sitting the test. The simulator runs the first-time adult form: 36 questions, 6 mistakes allowed, 83% to pass.
Source: California Driver's Handbook (DL 600, rev. 6/2025), the document the DMV writes the real test from. Edited by Fernando Aguilera. Aprobify is not affiliated with the California DMV.
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