# Calculating the total energy of freefall at different heights in Work And Energy – Class 9 Science Experiment

## Activity Name: Calculating the total energy of freefall at different heights in Work And Energy

### Activity Description:

In this experiment, we will calculate the total energy (potential energy and kinetic energy) of an object in freefall from different heights. The object has a mass of 20 kg, and we will drop it from various heights, recording the potential and kinetic energy values for each case. The acceleration due to gravity (g) will be taken as 10 m/s².

### Required Items:

1. Object with a mass of 20 kg
2. Measuring tape or ruler
3. Stopwatch or timer
4. Calculator
5. Table for recording data

### Step by Step Procedure:

1. Set up the experiment area with enough vertical space to drop the object from different heights safely.
2. Measure and mark the following heights: 1m, 2m, 3m, 4m, and any additional heights desired.
3. Drop the object from the 4m height and use a stopwatch to measure the time it takes to reach the ground.
4. Record the time in the table.
5. Calculate the potential energy at each height using the formula: Potential Energy (PE) = mass × gravitational acceleration (g) × height.
6. Record the potential energy values in the table.
7. Calculate the kinetic energy at each height using the formula: Kinetic Energy (KE) = 0.5 × mass × velocity².
8. The velocity can be calculated using the formula: velocity = height × gravitational acceleration (g) / time taken to fall.
9. Record the kinetic energy values in the table.
10. Repeat steps 3-9 for each height, dropping the object from 1m, 2m, 3m, and any other desired heights.
11. Tabulate all the calculated values for potential and kinetic energy in the respective columns of the table.

### Experiment Observations:

Note down your observations in table format:

### Precautions:

1. Ensure the experiment area is clear of any obstacles to avoid any accidents during the freefall.
2. Use a timer or stopwatch to accurately measure the time taken for the object to fall.
3. Handle the object with care to avoid damage or injury during the experiment.
4. Make sure to conduct the experiment in a controlled environment with minimal air resistance.

### Lesson Learnt from Experiment:

This experiment will help understand the concept of potential and kinetic energy and how they change as an object falls from different heights. It demonstrates the conversion of potential energy into kinetic energy as the object moves downward due to gravity. Additionally, it reinforces the principle of energy conservation, where the total energy remains constant throughout the freefall.