Free-Fall Calculator
d = ½ g t² and v = g t. Distance and final velocity for an object falling from rest.
Result
Distance fallen
44.145 m
Final velocity: 29.43 m/s (65.8 mph).
- Time3.0000 s
- Distance44.1450 m
- Gravity9.81 m/s²
- Final velocity29.4300 m/s
- Final v (mph)65.83
- Final v (km/h)105.95
Step-by-step
- d = ½gt² = 0.5 × 9.81 × 3² = 44.1450 m.
- v = gt = 9.81 × 3.0000 = 29.4300 m/s.
How to use this calculator
- Pick known: time or distance.
- Enter g (9.81 Earth, 1.62 Moon).
- Read the other + final velocity.
About this calculator
Object dropped from rest: d = ½gt², v = gt. Vacuum / no air resistance. Earth: g = 9.81 m/s². Falling from 100m: t ≈ 4.5s, v ≈ 44 m/s (98 mph). Real falls slow due to air resistance — terminal velocity for human ~55 m/s (120 mph). Galileo proved (1589, allegedly from Pisa Tower) that all objects fall at the same rate ignoring air — feathers and bowling balls.
Frequently asked
Yes. Real fall through air: small/dense objects (rock) close to vacuum; large/light (feather, paper) much slower.
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