Best examples of 3 examples of free fall experiments for students

When teachers talk about the best examples of 3 examples of free fall experiments, the classic ball drop is always on the list. It’s simple, visual, and works with almost any budget.

You release a small ball from rest, let it fall straight down, and measure how long it takes to hit the ground. From that, you can estimate the acceleration due to gravity, g ≈ 9.8 m/s² (about 32 ft/s²).

Basic setup

You need:

• A ball (tennis ball, rubber ball, or steel ball)
• A known drop height (for example, 2 m or 6 ft from a balcony or stairwell)
• A way to measure time: stopwatch, phone timer, or better, a high-speed video

Students mark the release point, measure the height with a tape measure, and run several trials. With a simple stopwatch, human reaction time introduces error, but that’s part of the learning: one of the best examples of experimental uncertainty they’ll see all year.

Data and analysis

If the ball starts from rest, the distance fallen is given by:

s = ½ g t²

So you can estimate g with:

g = 2s / t²

Have students:

• Take 5–10 trials for the same height
• Average the times
• Compute g from the averaged time
• Compare their value to the accepted 9.8 m/s²

This first experiment is the anchor in any set of examples of 3 examples of free fall experiments because it’s easy to run and exposes systematic errors: students may drop from slightly different heights, start/stop the timer late, or misread the tape.

For background on gravity values and how g varies slightly over Earth, you can point students to data from NASA and the U.S. Geological Survey (for example, the USGS gravity data overview gives real-world context).

2. Two-object drop: real examples that test “heavy objects fall faster”

One of the best examples of 3 examples of free fall experiments for breaking misconceptions is the two-object drop. The idea is simple: drop two objects of very different mass but similar shape at the same time and watch what happens.

Setup idea

Use:

• Two metal balls of different mass but same size, or
• A tennis ball and a slightly heavier rubber ball of similar size

Have students:

• Hold one object in each hand at the same height
• Release them at the same time
• Observe which hits the ground first

With careful releases and a short drop (around 1–2 m), they’ll see that both objects land almost simultaneously. This is one of the clearest real examples that, in the absence of significant air resistance, all objects experience the same gravitational acceleration.

Taking it further with video

To make this a more quantitative example of free fall experiments, record the drop using a smartphone in slow-motion mode (240 fps if available). Then:

• Step through the video frame by frame
• Track the vertical position of each ball versus time
• Compare their motion

Students will see nearly identical position vs. time curves. This experiment pairs nicely with the classic Apollo 15 hammer-and-feather demonstration on the Moon, where astronaut David Scott dropped a hammer and a feather in lunar vacuum and they hit the surface together. NASA has the video and explanation on its official site.

This two-object drop is one of the simplest examples of 3 examples of free fall experiments that connects classroom physics to historic space exploration.

3. Free fall with air resistance: coffee filter and paper experiments

If the first two examples of 3 examples of free fall experiments treat air resistance as a small correction, this one puts it center stage.

Coffee filters as a physics tool

Coffee filters are light, have a large surface area, and reach terminal velocity quickly. That makes them perfect for exploring how air resistance competes with gravity.

Try this:

• Drop a single coffee filter from a known height
• Then drop a stack of 2, 3, or 4 filters taped together from the same height
• Time each fall with a stopwatch or slow-motion video

Students will see that the heavier stack falls faster than a single filter, even though both are in free fall subject to gravity and drag. The net force is different because air resistance grows with speed and area.

A similar example of an air-resistance-heavy free fall experiment is to drop a flat sheet of paper and a crumpled ball of the same paper. The crumpled ball falls much faster because the effective cross-sectional area is smaller, so it experiences less drag.

Analyzing the motion

You can:

• Plot fall time vs. number of filters
• Discuss terminal velocity and how the upward drag force balances weight at constant speed
• Introduce the idea that drag often scales like v² at higher speeds

This is one of the best examples of free fall experiments for connecting basic kinematics to real-world motion like parachutes, skydiving, and even raindrop speeds. For more on drag and motion, the HyperPhysics resource at Georgia State University offers a solid conceptual overview.

4. Electromagnet release and photogate: a precision lab example

For high school or intro college courses, you can move from stopwatches to photogates and an electromagnet release. This is one of the best examples of 3 examples of free fall experiments when you want accurate, publishable-looking data.

How it works

• A small steel ball is held in place by an electromagnet connected to a circuit.
• When you cut the current, the ball is released.
• As it falls, it passes through one or more photogates (light beams connected to timers).

The timer starts when the current is cut or when the ball leaves a top photogate, and stops when the ball reaches a lower photogate or the floor sensor.

Why this is powerful

This setup reduces human reaction error and lets you:

• Measure time for several different heights
• Plot distance vs. time² and fit a straight line
• Extract g from the slope, often within a few percent of 9.8 m/s²

Students see how a well-designed example of free fall experiments can turn messy motion into clean linear graphs. You can also ask them to compare their measured g with the local value predicted by standard references, such as data compiled in physics handbooks and educational resources like MIT OpenCourseWare.

5. Smartphone video tracking: modern examples include app-based labs

In 2024–2025, many of the best examples of 3 examples of free fall experiments include smartphones, not just for timing but for full motion tracking.

Basic idea

• Tape a meter stick or yardstick vertically to a wall.
• Record a ball drop in front of the scale using a smartphone in slow motion.
• Import the video into a free tracking tool (for example, Tracker, a widely used open-source physics video analysis program).

Students click on the ball’s position frame by frame. The software then:

• Generates position vs. time data
• Computes velocity vs. time
• Lets them fit a straight line to velocity vs. time to estimate acceleration

This turns a simple ball drop into a data-rich example of free fall experiments, with hundreds of data points instead of a single time measurement.

Why this matters now

App-based labs align with current trends in physics education research, which emphasize authentic data analysis and modeling. Students can:

• Compare different heights in a single run
• See small deviations from perfect parabolas due to air resistance
• Export data to spreadsheets for deeper analysis

Educational groups and universities, such as the American Association of Physics Teachers (AAPT) and many .edu physics departments, now publish lab ideas that integrate smartphone sensors and video. These modern examples of free fall experiments help bridge the gap between textbook diagrams and real-world measurements.

6. Vacuum tube and feather: dramatic example of free fall without air

If you want a dramatic classroom demo, a vacuum tube free fall experiment is hard to beat. This is one of the best examples of 3 examples of free fall experiments for showing that air resistance is the only reason feathers and stones fall differently on Earth.

Typical setup

• A long transparent tube with a small rock and a feather inside
• A vacuum pump to remove most of the air

With air in the tube, the rock hits the bottom first; the feather drifts down slowly. Once the air is pumped out and the tube is evacuated, both objects fall together and hit the bottom at almost the same time.

This experiment is a classroom-scale echo of the Apollo 15 hammer-and-feather drop on the Moon, and it powerfully reinforces the idea that in true free fall, all objects accelerate at the same rate regardless of mass or composition.

If you don’t have access to a vacuum tube, showing verified video from university physics departments or NASA is a solid alternative. Many .edu sites host high-quality recordings of this exact example of free fall experiments.

7. Large-scale real examples: dropping objects from towers and bridges

So far, most of these examples of 3 examples of free fall experiments are classroom-sized. But real examples outside the lab can give students a sense of scale.

Teachers and outreach programs sometimes:

• Drop water balloons, weighted balls, or safe test objects from tall stairwells, theater catwalks, or controlled bridge sites.
• Use walkie-talkies or synchronized timers to coordinate release and timing.

With larger heights (say, 10–30 m or 30–100 ft), students can:

• See more pronounced curvature in position vs. time graphs
• Measure impact speeds using v ≈ √(2 g h)
• Discuss safety, permissions, and experimental design in real environments

These are some of the best examples of free fall experiments for connecting physics to engineering and safety questions (for example, why construction zones restrict access under work platforms). While not every school can run these outdoor experiments, even planning them on paper is a good exercise in thinking like experimental physicists.

8. Space-based examples: ISS, astronauts, and orbital free fall

Any list of the best examples of 3 examples of free fall experiments should end beyond Earth’s surface. Astronauts on the International Space Station (ISS) are not weightless because there is no gravity; they are in continuous free fall around Earth.

Conceptual experiment

• Imagine dropping a ball from a very tall tower.
• Increase the horizontal speed so much that as the ball falls, Earth’s surface curves away beneath it.
• The ball keeps missing the ground and orbits instead.

That’s essentially what the ISS is doing. Objects and astronauts inside are all falling together under gravity, so they appear to float relative to one another.

NASA frequently shares real examples of free fall experiments performed in microgravity, such as fluid behavior, combustion, and crystal growth. These are advanced, but they’re great discussion starters: free fall isn’t just a classroom stunt, it’s a central tool in modern space science. NASA’s educational pages at nasa.gov offer accessible explanations aimed at students and teachers.

Pulling it together: using multiple examples of 3 examples of free fall experiments in a course

To build a coherent unit on gravity and motion, you can sequence these experiments rather than using just a single example of free fall experiments:

• Start with the classic ball drop to introduce constant acceleration.
• Add the two-object drop to challenge the “heavy falls faster” myth.
• Use coffee filters and paper to bring in air resistance and terminal velocity.
• Move to electromagnet and photogates or smartphone tracking for high-precision measurements.
• Show or discuss vacuum tube and space-based real examples to connect classroom physics to cutting-edge science.

Across these examples of 3 examples of free fall experiments, students see the same core ideas—gravity, acceleration, and motion under constant force—played out in different contexts and at different levels of precision. That repetition with variation is what really cements the physics.

FAQ: common questions about free fall experiments

Q1. What are some simple examples of free fall experiments for beginners?
Simple examples include a single ball drop from a measured height, a two-object drop with balls of different mass, and a paper vs. crumpled paper drop to highlight air resistance. These can be done with basic tools: a tape measure, a stopwatch, and a smartphone camera.

Q2. How accurate can a basic example of free fall experiment be?
With a stopwatch and careful technique, students can often measure g within 10–20%. Using photogates or smartphone video tracking, that can improve to a few percent. The limiting factors are timing precision, accurate height measurement, and controlling air currents and starting conditions.

Q3. Do all examples of free fall experiments ignore air resistance?
No. The earliest examples often assume air resistance is small, but many of the best examples of free fall experiments intentionally focus on drag, such as coffee filter drops or feather-and-rock comparisons in air and vacuum. Part of learning physics is knowing when you can ignore air resistance and when you can’t.

Q4. Are there real examples of free fall outside the lab?
Yes. Skydivers before parachute deployment, objects dropped from towers or bridges, and even satellites in orbit are all in free fall. Astronauts on the ISS are in continuous free fall around Earth, which is why they experience apparent weightlessness.

Q5. Where can I find more detailed guidance on designing physics labs?
University physics departments and professional organizations like the American Association of Physics Teachers often publish lab manuals and teaching resources. You can explore open materials from institutions such as MIT and Harvard (for example, via Harvard’s physics teaching resources) and general science education content from U.S. agencies like NASA.