describe an experiment to determine the acceleration of free fall using a falling object

Equations of Motion: Determining the Acceleration of Free Fall 🚀

Experiment Overview

In this experiment you will find the value of the acceleration due to gravity, g, by dropping a small object from a known height and measuring the time it takes to hit the ground.

Materials Needed

• 1 metre ruler or measuring tape
• 1 small ball (e.g., a tennis ball)
• Stopwatch (or a phone with a stopwatch app)
• Notebook and pen
• Safety goggles (optional but recommended)

Procedure

1. Choose a safe drop point, such as a balcony or a high step.
2. Measure a height of 1 m from the drop point to the ground. Mark this height on the wall or floor.
3. Hold the ball at the marked height, keeping your hand still.
4. Start the stopwatch as soon as you release the ball.
5. Stop the stopwatch when the ball makes contact with the ground.
6. Record the time in seconds. Repeat the drop 5–10 times to get an average.

Physics Behind the Experiment

When an object falls freely near the Earth’s surface, its motion is described by the equation:

where y is the distance fallen, g is the acceleration due to gravity, and t is the time of fall. Rearranging gives:

So, by measuring y (1 m) and t (your stopwatch reading), you can calculate g.

Recording Data

Calculating g

For each trial, use the formula:

Compute g for each time measurement, then average the results to obtain the best estimate.

Safety Tips

• Never drop the ball from a height that could injure someone below.
• Wear safety goggles if you are working near windows or in a crowded area.
• Ensure the drop area is clear of obstacles.

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