Horizontal Projectile Motion Calculator
An object launched horizontally from a height — how far it travels, how long it falls, and how fast it lands.
Rolled off a table, thrown straight out from a cliff.
How the horizontal projectile motion calculator works
A horizontal launch is the simplest projectile case: the vertical motion is a plain free fall, entirely independent of how fast the object was moving sideways.
That independence is the famous result — a bullet fired horizontally and one dropped from the same height hit the ground at the same moment. Fall time depends only on the height: t = √(2h/g).
Formula: t = √(2h/g); x = v t
Worked examples
| Inputs | Horizontal distance | Note |
|---|---|---|
| 10 m up at 5 m/s | 7.14 m | falls 1.43 s, lands 7.1 m out |
| Dropped, not thrown | 0 m | same fall time, no distance |
| A fast launch | 71.404 m | ten times the distance, identical fall time |
FAQFrequently asked questions
Does a faster launch take longer to fall?
No. Fall time depends only on the height. A bullet fired horizontally and one dropped hit the ground together.
How long to fall 10 metres?
About 1.43 seconds, whatever the horizontal speed.
Why is the impact angle not 45°?
Because the vertical speed builds up while the horizontal one stays fixed. The angle steepens with height and flattens with launch speed.
Does this include air resistance?
No. It matters for light objects and for falls beyond about 20 metres, where drag becomes significant.
What if the object is launched at an angle?
Use the full projectile motion calculator, which handles any launch angle and starting height.
Where these figures come from
- NIST — CODATA 2018 fundamental physical constants — G, g₀, R, c
- NIST Special Publication 811 — Guide for the use of the International System of Units — unit conversions
- The Engineering ToolBox — material properties — specific heats, expansion coefficients, densities
- National Physical Laboratory — the UK's national measurement institute
Last checked: September 2026. Constants are the CODATA 2018 values; formulas are the standard textbook forms.