Free-fall time

t=sqrt(2h/g) and impact speed under constant g.

SIDUS educational calculator. Category utilities. Tags: aero, ballistics, entry, utilities. Pure SI. Not flight software.

Formula

t = √(2h/g) · v = √(2gh)

Constant-g free fall

Primary sources

• NASA Glenn Research Center: Beginner’s Guide to Aeronautics (NASA GRC): Ideal rocket equation, specific impulse, thrust equation, dynamic pressure education pages.
• Orbital Mechanics for Engineering Students (Howard D. Curtis): Textbook derivations for Hohmann, vis-viva, rocket equation, elements.

How do AI agents use this tool?

Read /llms.txt or call https://sidus.tools/api/mcp. Open the interactive page for live SI inputs.