Gerak Lurus • Part 2: Contoh Soal Gerak Lurus Beraturan (GLB) & Gerak Lurus Berubah Beraturan (GLBB)

Introduction

This tutorial provides a comprehensive guide on solving problems related to uniform linear motion (Gerak Lurus Beraturan - GLB) and uniformly accelerated linear motion (Gerak Lurus Berubah Beraturan - GLBB). Based on the content from a YouTube video by Jendela Sains, we will discuss four examples that illustrate these concepts, including how to determine acceleration, distance traveled, and deceleration.

Step 1: Understand the Basics of GLB and GLBB

Before diving into the examples, it's important to understand the key principles:

• GLB refers to motion at a constant speed, where the distance covered over time is linear.
• GLBB involves acceleration or deceleration, meaning the speed changes over time.

Practical Tips

• Familiarize yourself with the formulas:
  • For GLB: ( s = vt ) (distance = speed × time)
  • For GLBB:
    • ( s = v_0t + \frac{1}{2}at^2 ) (distance = initial velocity × time + 0.5 × acceleration × time²)
    • ( v = v_0 + at ) (final velocity = initial velocity + acceleration × time)

Step 2: Solve Example Problem 2

Problem Statement

Determine the acceleration and distance traveled by a car undergoing uniformly accelerated motion.

Solution Steps

1. Identify given data:

   • Initial velocity ( v_0 )
   • Time ( t )
   • Final velocity ( v )

2. Use the formula for acceleration: [ a = \frac{v - v_0}{t} ]

3. Calculate distance using: [ s = v_0t + \frac{1}{2}at^2 ]

Common Pitfalls

• Ensure units are consistent (e.g., all in meters and seconds).
• Double-check calculations for accuracy.

Step 3: Solve Example Problem 3

Problem Statement

Calculate the acceleration of an object when the initial speed, time, and distance traveled are known.

Solution Steps

1. List known variables:

   • Initial velocity ( v_0 )
   • Time ( t )
   • Distance ( s )

2. Rearrange the distance formula to isolate acceleration: [ a = \frac{2(s - v_0t)}{t^2} ]

3. Plug in the values to find acceleration.

Step 4: Solve Example Problem 4

Problem Statement

Determine the deceleration and time required for a car to stop.

Solution Steps

1. Gather data:

   • Initial speed ( v_0 )
   • Final speed ( v = 0 ) (since the car stops)
   • Distance ( s )

2. Use the formula for deceleration: [ a = \frac{-v_0^2}{2s} ]

3. Calculate time using: [ t = \frac{v - v_0}{a} ]

Step 5: Solve Example Problem 5

Problem Statement

Identify the type of motion, acceleration, and total distance based on a velocity-time graph.

Solution Steps

1. Analyze the graph to determine:

   • The shape of the graph indicates the type of motion (constant vs. changing speed).
   • Calculate the slope for acceleration.

2. Use the area under the graph to find the total distance:

   • For a rectangular area: ( s = \text{base} \times \text{height} )
   • For a triangular area: ( s = \frac{1}{2} \times \text{base} \times \text{height} )

Conclusion

Understanding GLB and GLBB is essential for solving motion problems in physics. By following the steps outlined in this tutorial, you can effectively analyze motion scenarios using given data and applicable formulas. Practice with these example problems to strengthen your grasp of the concepts, and consider exploring more complex scenarios or variations in motion.