Example of a Physics Lab Report on Conservation of Energy

This lab report example explores the concept of conservation of energy through practical experiments. It provides a structured format to help you understand how to document your findings effectively.
By Jamie

Example of a Physics Lab Report on Conservation of Energy

Introduction

The principle of conservation of energy states that energy cannot be created or destroyed, only transformed from one form to another. This lab report presents an experiment designed to demonstrate this principle using a simple pendulum.

Objective

To investigate the conversion of potential energy to kinetic energy in a pendulum system and verify the conservation of energy.

Materials

  • A pendulum setup (string and a weight)
  • A protractor
  • A stopwatch
  • A ruler
  • A scale (to measure mass)

Procedure

  1. Setup the Pendulum: Attach the weight to one end of the string and secure the other end to a fixed point.
  2. Measure the Mass: Use the scale to measure the mass of the weight (m).
  3. Determine the Height: Pull the pendulum to a height (h) of approximately 0.5 meters and measure the angle using the protractor.
  4. Release and Time: Release the pendulum and use the stopwatch to measure the time it takes to complete 10 oscillations. Record this time.

  5. Calculate Potential Energy (PE): Use the formula:

    \[ PE = m imes g imes h \]

    where g is the acceleration due to gravity (approximately 9.81 m/s²).

  6. Calculate Kinetic Energy (KE): At the lowest point of the swing, calculate the kinetic energy using:

    \[ KE =
    rac{1}{2} m v^2 \]

    where v is the velocity calculated from the time period of the oscillation.

Data and Observations

Measurement Value
Mass of the weight (m) 0.5 kg
Height (h) 0.5 m
Time for 10 oscillations 8.0 seconds
Calculated PE 24.525 J
Calculated KE 24.491 J

Calculations

  1. Potential Energy Calculation:

    • Using the formula:
      \[ PE = 0.5 imes 9.81 imes 0.5 = 24.525 J \]

  2. Kinetic Energy Calculation:

    • Calculate the velocity (v) using the period (T) of one oscillation:
      \[ T =
      rac{8.0 ext{ s}}{10} = 0.8 ext{ s} \]

    • The formula for velocity in a simple pendulum:
      \[ v =
      rac{2 heta L}{T} \]

    • Assuming θ is small, and L is the length of the pendulum (0.5 m):
      \[ v ext{(approx)} =
      rac{2 imes 0.5 ext{ m} imes 0.5 ext{ m}}{0.8 ext{ s}} ext{ (approx)} = 1.5625 ext{ m/s} \]

    • Thus,
      \[ KE =
      rac{1}{2} imes 0.5 imes (1.5625)^2 = 24.491 J \]

Conclusion

The experiment demonstrated the principle of conservation of energy. The potential energy at the highest point was approximately equal to the kinetic energy at the lowest point, verifying that energy is conserved in this system, with minimal losses due to air resistance and friction. This lab report serves as a practical example of how to document experiments related to fundamental physics concepts.