Free Fall Simulator

Free fall is motion under gravity alone — no air, no thrust, no support. Galileo's famous insight was that all objects fall at the same rate regardless of mass, because gravitational mass and inertial mass cancel out. Drop an object from any height and verify it yourself: time the fall and check the impact speed.

Drop height 60 m

Fall time 3.50 sImpact speed 34.3 m/sElapsed 0.00 s

Controls

Drop height: The height above the ground where the object is released, in meters.
Drop: Release the object from rest.
Reset: Return to the starting height.

The physics

s = \frac{1}{2}gt^2

Distance fallen from rest

v = \sqrt{2gs}

Impact speed

t = \sqrt{\frac{2h}{g}}

Fall time from height h

Assumptions

No air resistance (vacuum)
Dropped from rest (initial velocity zero)
g = 9.81 m/s²
Constant g over the fall distance

Guided activity

Drop from 20 m and record the fall time and impact speed.
Double the height to 40 m. Does the fall time double? Check the square-root relationship.
Compare the impact speed from 5 m vs 20 m — by what factor does it grow?
Explain in your own words why the mass of the object never appears in your results.

Challenge questions

A rock and a feather fall together in a vacuum chamber — who lands first, and why does air change the everyday answer?
Derive the fall-time formula from the equations of motion, starting from s = ut + ½at².
If g were 1.62 m/s² (the Moon), how would the 20 m fall time change?