Energy Skate Park App1 Lab 1 Answer Key

Energy SkatePark App1 Lab 1 Answer Key: A Complete Guide

The Energy Skate Park simulation, part of the PhET App1 Lab 1, asks students to explore how kinetic and potential energy transform as a skater moves through a virtual track. This article provides a detailed walkthrough of the lab, explains the underlying physics, and supplies the Energy Skate Park App1 Lab 1 answer key that instructors and learners can use to verify their results. By following the structured steps below, you will gain a clear understanding of energy conservation, learn how to manipulate variables, and be equipped to interpret the data the simulation generates. ## Lab Overview and Learning Objectives

The primary goal of Lab 1 is to investigate the relationship between an object’s height, speed, and energy forms. Students are expected to: - Identify kinetic energy (KE) and gravitational potential energy (PE) at various points on the track. - Observe how energy converts between KE and PE while total mechanical energy remains constant (ignoring friction).

• Apply the conservation of energy principle to predict the skater’s speed at different elevations.

The lab also reinforces scientific inquiry skills such as hypothesis formation, data collection, and graphical analysis.

Key Concepts and Terminology

Before diving into the experiment, become familiar with the following terms:

• Kinetic Energy (KE): The energy of motion, calculated as ( KE = \frac{1}{2}mv^2 ). - Potential Energy (PE): Stored energy due to position, given by ( PE = mgh ), where ( g ) is the acceleration due to gravity.
• Total Mechanical Energy (TME): The sum of KE and PE, which stays constant in an ideal, frictionless system.
• Friction: A non‑conservative force that can dissipate energy as heat, affecting real‑world outcomes.

Understanding these concepts is essential for interpreting the Energy Skate Park App1 Lab 1 answer key accurately.

Step‑by‑Step Guide to Completing Lab 1

Below is a concise, numbered procedure that aligns with the typical classroom instructions. Follow each step and record your observations in a lab notebook or digital worksheet.

1. Launch the Simulation

   • Open the PhET “Energy Skate Park” simulation and select the “Intro” mode.
   • Choose the “Energy Skate Park: Basics” tab if you are using the newer interface.

2. Set the Skater’s Mass

   • Click the “Mass” slider and choose a value (e.g., 100 kg).
   • Keep this mass constant throughout the experiment to isolate the effect of height.

3. Adjust the Track Height

   • Drag the “Height” slider to create a starting point for the skater.
   • Record the height value (in meters) for each trial.

4. Release the Skater

   • Position the skater at the top of the hill and click the “Play” button to let them descend.
   • Observe the motion and note the speed at the bottom of the track. 5. Measure Speed
   • Use the on‑screen “Speed” indicator or the built‑in data table to capture the skater’s velocity at key points (top, middle, bottom).

5. Repeat with Different Heights

   • Change the starting height and repeat steps 3‑5 at least three times for each height to ensure reliability.

6. Introduce Friction (Optional)

   • Activate the “Friction” slider and set it to a low value (e.g., 0.1).
   • Observe how the skater’s speed decreases and discuss the energy loss as heat.

7. Graph Energy Values

   • Use the “Graph” tab to plot KE, PE, and TME versus position.
   • Identify patterns that illustrate energy conservation. ## Interpreting the Data

When you complete the measurements, you will notice that the total mechanical energy remains nearly constant for a frictionless track. However, when friction is enabled, the TME gradually declines, indicating energy conversion to thermal forms.

• At the highest point: PE is at its maximum, KE is zero.
• At the lowest point: KE peaks, PE reaches its minimum.
• Mid‑track points: Both KE and PE share intermediate values, but their sum stays constant (ignoring friction).

These observations align with the Energy Skate Park App1 Lab 1 answer key and reinforce the principle that energy cannot be created or destroyed, only transformed.

Energy Skate Park App1 Lab 1 Answer Key

Below is a consolidated answer key that covers typical student responses, calculations, and interpretations. Use this as a reference to check your work.

1. Calculating Kinetic and Potential Energy

If friction is enabled, subtract the observed energy loss from the TME to estimate the amount dissipated as heat.

2. Sample Observations

• Height 2.0 m: Measured speed ≈ 6.2 m/s → KE ≈ ½ × 100 × 6.2² ≈ 1930 J (close to PE).
• Height 3.5 m: Measured speed ≈ 8.3 m/s → KE ≈ 3450 J (matches PE).
• Height 5.0 m: Measured speed ≈ 9.9 m/s → KE ≈ 4900 J (matches PE).

These

...values confirm the near-perfect conversion between potential and kinetic energy under ideal conditions. Minor discrepancies—typically within 1–2%—can be attributed to rounding in speed readings or simulation precision, but they do not undermine the core principle.

3. Analyzing Frictional Effects

When friction is introduced (e.g., slider set to 0.1), the total mechanical energy (TME) decreases steadily along the track. For a 5.0 m height:

• Initial TME = 4900 J
• At bottom, KE might measure ~4750 J
• Energy lost to heat = 4900 J – 4750 J = 150 J

This loss illustrates the second law of thermodynamics: mechanical energy dissipates as thermal energy, increasing entropy. The skater slows more gradually, and the speed at the bottom is less than the frictionless prediction.

4. Graphical Patterns

The position vs. energy graph typically shows:

• PE decreasing as a concave-down curve (high at start, low at bottom).
• KE increasing as a concave-up curve (zero at start, peak at bottom).
• TME as a horizontal line (frictionless) or a gently sloping downward line (with friction).

The sum of KE and PE at any point equals the initial PE (if no friction), visually confirming energy conservation.

Conclusion

This lab investigation using the Energy Skate Park simulation robustly demonstrates the law of conservation of mechanical energy in an isolated system. Under frictionless conditions, potential energy transforms completely into kinetic energy, maintaining constant total mechanical energy—a principle reflected in the symmetrical interchange of energy forms along the track. Introducing friction reveals energy’s transformation into non-mechanical forms, aligning with real-world scenarios where dissipative forces are unavoidable. The quantitative measurements and graphical analyses reinforce that while energy can change forms, the total energy in a closed system remains unchanged. These findings not only validate foundational physics concepts but also highlight the utility of simulations in exploring idealized versus realistic systems, deepening understanding of energy dynamics in engineering and natural phenomena.