Free Fall Calculator
Find fall time and impact speed from a height, with a distance–time table.
Step-by-step working
- t = √(2h/g) = √(2 × 20 / 9.80665) = 2.0196 s
- v = g t = 19.8057 m/s
| t (s) | distance (m) | speed (m/s) |
|---|---|---|
| 0 | 0 | 0 |
| 0.252 | 0.313 | 2.476 |
| 0.505 | 1.25 | 4.951 |
| 0.757 | 2.813 | 7.427 |
| 1.01 | 5 | 9.903 |
| 1.262 | 7.813 | 12.379 |
| 1.515 | 11.25 | 14.854 |
| 1.767 | 15.313 | 17.33 |
| 2.02 | 20 | 19.806 |
Mathematical Formula
Overview & Explanation
In free fall an object accelerates uniformly at g.
How It Works
- Solve h = ½gt² for t.
- Speed = g t.
Practical Applications
- Safety estimates.
- Physics homework.
Example 1: 20 m on Earth
≈ 2.02 s.
Inputs
Drop height (m): 20 · Gravity (body): Earth (9.80665 m/s²)
Step 1
t = √(2h/g) = √(2 × 20 / 9.80665) = 2.0196 s
Step 2
v = g t = 19.8057 m/s
Fall time
Result
Example 2: 20 m on Mars
Lower g.
Inputs
Drop height (m): 20 · Gravity (body): Mars (3.71 m/s²)
Step 1
t = √(2h/g) = √(2 × 20 / 3.71) = 3.2835 s
Step 2
v = g t = 12.182 m/s
Fall time
Result
How it's calculated & sources
t = √(2h/g); v = g t (no air resistance).
Frequently Asked Questions
Do heavier objects fall faster?
Terminal velocity?
Thrown downward?
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