Physics Lab Report Examples: Simple Harmonic Motion

Explore practical examples of physics lab reports focused on simple harmonic motion.
By Jamie

Introduction to Simple Harmonic Motion

Simple harmonic motion (SHM) is a type of periodic motion where an object oscillates back and forth around an equilibrium position. It is characterized by its sinusoidal nature and is fundamental in various physical systems, including springs, pendulums, and waves. Understanding SHM is crucial for students in physics, as it lays the groundwork for more complex concepts in dynamics and wave mechanics.

Example 1: Investigating the Period of a Mass-Spring System

Context

This experiment aims to determine how the mass attached to a spring affects the period of oscillation. It helps in understanding Hooke’s Law and the principles of SHM.

A spring with a known spring constant is used, and various masses are attached to observe the effect on the time period of oscillation.

Example

  1. Materials Needed:

    • Spring with a known spring constant (k)
    • Various masses (100g, 200g, 300g, 400g)
    • Stopwatch
    • Ruler
    • Clamp stand

  2. Procedure:

    • Set up the spring vertically using a clamp stand.
    • Attach a mass to the spring and allow it to come to rest.
    • Pull the mass down slightly and release it to initiate oscillation.
    • Use a stopwatch to time 10 complete oscillations and record the time.
    • Repeat for each mass, ensuring to record the time for each trial.

  3. Data Collection:

    Mass (kg) Time for 10 Oscillations (s) Period (T = Time/10) (s)
    0.1 12.5 1.25
    0.2 17.6 1.76
    0.3 21.2 2.12
    0.4 24.8 2.48

  4. Analysis:

    • Calculate the average period for each mass.
    • Plot a graph of mass vs. period squared (T²) to analyze the linear relationship.
    • The slope of the graph will help determine the spring constant using the formula: T² = (4π²/k)m.

Notes

  • Ensure that the mass is attached securely to avoid any errors due to slippage.
  • Consider variations such as using different spring constants or altering the amplitude of oscillation.

Example 2: The Pendulum Experiment

Context

This experiment focuses on a simple pendulum to explore how the length of the pendulum affects its period of oscillation. This example reinforces the concept of SHM in a real-world context.

Example

  1. Materials Needed:

    • String (varying lengths: 0.5m, 1.0m, 1.5m)
    • Small weight (e.g., a washer)
    • Protractor
    • Stopwatch
    • Ruler

  2. Procedure:

    • Measure and cut the string to the desired lengths.
    • Attach the weight to one end of the string and secure the other end so that it can swing freely.
    • Pull the pendulum to a small angle (less than 15°) and release it.
    • Time 10 complete oscillations using the stopwatch and record the time.
    • Repeat for each length of the pendulum.

  3. Data Collection:

    Length (m) Time for 10 Oscillations (s) Period (T = Time/10) (s)
    0.5 6.3 0.63
    1.0 9.8 0.98
    1.5 12.5 1.25

  4. Analysis:

    • Calculate the average period for each length.
    • Graph the length of the pendulum vs. period squared (T²) to observe the relationship.
    • The theoretical relationship can be compared with the experimental data using the formula: T = 2π√(L/g).

Notes

  • Ensure the angle of release is small to maintain the SHM approximation.
  • Variations can include testing different weights or angles of release.

Example 3: Damped Oscillations in a Spring-Mass System

Context

This experiment examines how damping affects the motion of a spring-mass system, providing insights into real-world applications like car suspensions and seismology.

Example

  1. Materials Needed:

    • Spring with a known spring constant (k)
    • Mass (200g)
    • Damping medium (e.g., water, air resistance)
    • Stopwatch
    • Ruler

  2. Procedure:

    • Set up the spring vertically and attach the mass.
    • Pull the mass down and release it to initiate oscillation.
    • Introduce damping by placing the mass in water or adjusting the air resistance.
    • Time the oscillations until the motion ceases and record the time for a set number of oscillations.

  3. Data Collection:

    Damping Medium Time for 5 Oscillations (s) Period (T = Time/5) (s)
    Air 10.0 2.00
    Water 15.5 3.10

  4. Analysis:

    • Compare the periods in air vs. water and discuss the effects of damping on oscillation.
    • Use theoretical models to explain why damping occurs and its implications in engineering designs.

Notes

  • Ensure consistent damping conditions for accurate comparisons.
  • Consider variations such as different mass values or damping mediums for further exploration.