Gerak Parabola • Part 1: Konsep, Skema, dan Rumus Gerak Parabola

Introduction

This tutorial covers the fundamental concepts of projectile motion, often referred to as "gerak parabola" in Indonesian. We will explore the key definitions, diagrams, and formulas necessary to understand and analyze projectile motion, particularly focusing on aspects like maximum height, time to reach the highest point, and the total distance traveled before hitting the ground.

Step 1: Understand the Concept of Projectile Motion

• Projectile motion involves the motion of an object thrown into the air, influenced by gravity.
• The path of the object forms a parabola, which can be analyzed using physics principles.
• Key variables include:
  • Initial velocity (v₀)
  • Launch angle (θ)
  • Acceleration due to gravity (g, approximately 9.81 m/s²)

Step 2: Visualize the Motion with a Diagram

• Create a sketch of the projectile's trajectory, highlighting:
  • The launch point
  • The peak of the trajectory (highest point)
  • The landing point
• Mark key positions on the diagram:
  • Initial position
  • Maximum height
  • Final position when the object hits the ground

Step 3: Calculate Initial Variables

• At the starting position (t=0):
  • Identify the initial velocity components:
    • Horizontal velocity (v₀x) = v₀ * cos(θ)
    • Vertical velocity (v₀y) = v₀ * sin(θ)
• These components will help in calculating other necessary parameters.

Step 4: Determine Key Parameters at Various Points

1. At the Highest Point

   • The vertical velocity (v_y) becomes zero.
   • Use the formula for maximum height (H):

     H = (v₀y²) / (2g)
     

2. Time to Reach the Highest Point (t_peak)

   • Calculate using:

     t_peak = v₀y / g
     

3. Total Time of Flight (t_total)

   • Since the time to go up is equal to the time to come down:

     t_total = 2 * t_peak
     

4. Total Horizontal Distance (Range)

   • Calculate the total distance traveled using:

     Range = v₀x * t_total
     

Step 5: Evaluate the Impact of Launch Angle

• The launch angle significantly affects the range and height:
  • A 45-degree angle maximizes distance for a given initial speed.
  • Lower angles result in shorter ranges, while higher angles increase height but reduce range.

Step 6: Analyze Common Problems

• Review typical questions that arise from projectile motion:
  • How long does it take for the object to hit the ground?
  • What is the maximum height reached?
  • How far does the object travel horizontally before landing?

Conclusion

Understanding the concepts and calculations related to projectile motion is key for solving problems in physics. Practice using these formulas and concepts with various initial velocities and angles to reinforce your knowledge. For further study, consider exploring additional parts of the series that delve into problem-solving and specific applications of projectile motion.