Free Fall Calculator
Calculate free-fall time, impact speed, initial-velocity effects, and planet-gravity scenarios from a drop height.
Check Free Fall Calculator
Result interpretation
Downward initial velocity is positive; a negative value represents an upward throw before the fall.
The calculator solves the positive time root, then reports impact speed.
- 1Convert the selected height to 45 m.
- 2Use downward initial velocity v0 = 0 m/s and g = 9.8067 m/s^2.
- 3Solve h = v0*t + 0.5*g*t^2 for the positive impact time.
- 4Read the impact speed from v = sqrt(v0^2 + 2gh).
Reusable output
Copy the current setup and result into a lab note or homework check.
Free fall setup: height 45 m (45 m), initial velocity 0 m/s downward. Gravity: 9.8067 m/s^2. Time to impact: 3.0294 s. Impact speed: 29.7086 m/s (106.9508 km/h, 66.4563 mph).
Formula result
Check before you use it
What the numbers show
The result estimates how long the fall takes and how fast the object would be moving on impact in the ideal model.
Use free fall calculator for drop-height checks, impact-speed baselines, planet-gravity comparisons, and introductory kinematics problems.
Real impacts in air will often be slower than the ideal estimate.
Copy-ready formula handoff
Use this after solving the live calculator result, then paste the answer into a lab note, homework check, or engineering review.
h = v0*t + 0.5*g*t^2, v = sqrt(v0^2 + 2gh)
- Time to impact: Time needed to fall from the stated height.
- Impact velocity: Speed reached just before impact in the ideal model.
- Drop height: Vertical drop distance after unit conversion.
- Initial velocity: Starting downward velocity; use a negative value for an upward throw.
- Air resistance is ignored.
- Downward velocity is treated as positive in the calculator setup.
- Entering an upward throw as positive when the page convention treats downward velocity as positive.
- Using horizontal travel distance as the drop height in the vertical-motion equation.
Free Fall Calculator result: [paste the solved value from the calculator above]. Formula used: h = v0*t + 0.5*g*t^2, v = sqrt(v0^2 + 2gh) Inputs checked: Time to impact, Impact velocity, Drop height, Initial velocity. Assumptions: Air resistance is ignored. Downward velocity is treated as positive in the calculator setup. Worked example: 45 m Earth drop from rest. Enter h = 45 m, v0 = 0 m/s, and Earth gravity. Solve the positive time root from h = v0*t + 0.5*g*t^2. Use v = sqrt(v0^2 + 2gh) for impact speed. Next check: Entering an upward throw as positive when the page convention treats downward velocity as positive.
Equation context
Built for drop-height checks, impact-speed baselines, planet-gravity comparisons, and introductory kinematics problems. This page pairs the live calculator with the governing formula, variable glossary, and a worked example so the result is easier to trust and reuse.
Quick entry points
Use the calculator to verify arithmetic after you set up the formula yourself.
Change one input at a time to see which variable is driving the result.
Review the formula notes before using the answer in a lab or design check.
Variables to track
Time needed to fall from the stated height. Unit: s.
Speed reached just before impact in the ideal model. Unit: m/s.
Vertical drop distance after unit conversion. Unit: m.
Starting downward velocity; use a negative value for an upward throw. Unit: m/s.
Local gravitational acceleration. Unit: m/s^2.
Formula method and unit assumptions
Formula and example
Worked example
45 m Earth drop from rest
- 1Enter h = 45 m, v0 = 0 m/s, and Earth gravity.
- 2Solve the positive time root from h = v0*t + 0.5*g*t^2.
- 3Use v = sqrt(v0^2 + 2gh) for impact speed.
Adding an initial downward velocity shortens the impact time, while lower gravity stretches the same drop over a longer interval.
Assumptions
Common mistakes
Related formula checks
Equation context and next checks
Formula and variable setup for Free Fall Calculator
Calculate free-fall time, impact speed, initial-velocity effects, and planet-gravity scenarios from a drop height. The page is designed to help you move from the known values to the correct formula without rebuilding the derivation every time.
For free fall calculator, the safest workflow is to confirm the unit system first, then map each symbol to the physical quantity in your problem statement before solving.
- t: Time to impact (s) - Time needed to fall from the stated height.
- v: Impact velocity (m/s) - Speed reached just before impact in the ideal model.
- h: Drop height (m) - Vertical drop distance after unit conversion.
- v0: Initial velocity (m/s) - Starting downward velocity; use a negative value for an upward throw.
- g: Gravity (m/s^2) - Local gravitational acceleration.
How to read the result
The result estimates how long the fall takes and how fast the object would be moving on impact in the ideal model.
This tool is especially useful for drop-height checks, impact-speed baselines, planet-gravity comparisons, and introductory kinematics problems. The output becomes more trustworthy when you compare nearby cases instead of relying on one single run.
- Initial velocity support
- Planet gravity presets
- Copyable impact summary
Assumptions and limits
The calculator applies the standard textbook relation for this topic, which makes it a strong first-pass answer but not always a full real-world model.
Before you use the result in a lab, design review, or report, check whether the simplified assumptions still match the physical system you care about.
- Air resistance is ignored.
- Downward velocity is treated as positive in the calculator setup.
- Gravity is constant over the drop height.
Quick glossary
Time needed to fall from the stated height.
Speed reached just before impact in the ideal model.
Vertical drop distance after unit conversion.
A simplified physics model that omits secondary effects so the first-order relationship is easier to inspect.
Formula checks before using the result
Formula questions
Checks before using the result
When should I use the free fall calculator?
Use free fall calculator for drop-height checks, impact-speed baselines, planet-gravity comparisons, and introductory kinematics problems, especially when the governing formula is already known and the main need is a fast, transparent calculation.
What is the main thing the free fall calculator tells me?
The result estimates how long the fall takes and how fast the object would be moving on impact in the ideal model.
What can make the free fall calculator answer inaccurate?
The answer is exact for the formula and assumptions on the page, but it can drift when the real system violates those assumptions. Common limits include Air resistance is ignored. Downward velocity is treated as positive in the calculator setup. Gravity is constant over the drop height.
Formula references and related examples
Formula Basis