Freely Falling Bodies (Gravity)

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Subject: Physics

Semester: 1

Period: 2

Week: 10

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School Name:

Teacher’s Name:

Subject: Physics

Grade Level: Grade 10

Week & Period: Week 10, Period II

Date:

Sub-topic: Freely Falling Bodies (Gravity)

Learning Objectives:
By the end of this lesson, learners should be able to:

1. Explain the concept of free fall and gravitational acceleration.
2. Apply motion equations to freely falling bodies.
3. Conduct and interpret a basic experiment on falling objects.
4. Calculate displacement, velocity, and time for free fall problems.

Instructional Materials:

• Stopwatch
• Meter rule
• Small ball or stone
• Chalk or marker
• Chart showing value of g (9.8 m/s²)

Anticipation (Warm-Up):
Ask:

• “What happens when you drop a ball from a height?”
• “Why do all objects fall downward?”
  Introduce gravity as the force responsible for free fall.

Building Knowledge:

1. Free Fall:
   • Motion under the influence of gravity alone
   • No air resistance considered
   • g = 9.8 m/s² (standard acceleration due to gravity)
2. Equations for Free Fall:
   • v = gt (if starting from rest)
   • s = ½gt²
   • v² = 2gs

Example 1:
An object is dropped from a height and falls freely for 3 seconds.

• v = gt = 9.8 × 3 = 29.4 m/s
• s = ½ × 9.8 × 3² = 44.1 m

Example 2:
Find the time it takes for an object to fall 20 m.

• s = ½gt² → 20 = ½ × 9.8 × t²
• t² = 40 ÷ 9.8 = 4.08 → t ≈ 2.02 s

Experiment:

• Drop a ball from a height (2–3 m)
• Time the fall using stopwatch
• Compare experimental time with calculated time using s = ½gt²
• Repeat 3 times and find the average

Activities:

• Solve numerical problems on free fall
• Draw and label motion diagrams for falling objects
• Graph velocity vs. time for a free-falling object

Assessment:
Oral:

1. What is the value of g on Earth?
2. What is free fall?

Written:

1. A body falls freely for 4 seconds. Find its final velocity and distance fallen.
2. How long does it take an object to fall 80 m?

Homework:

1. A stone dropped from a window hits the ground in 5 seconds. Find how far it fell.
2. If a body falls 98 m, what is its final velocity?
3. State two differences between free fall and general motion.

Expanded Notes:

• All bodies fall at the same rate if air resistance is neglected
• Gravity always acts downward
• These equations apply only when object falls from rest and under gravity alone

Differentiation:

• Visual learners: motion diagrams and fall graphs
• Practical learners: real-life experiment
• Learners needing support: step-by-step guided calculations

Teacher’s Reflection:

• Did learners grasp the link between gravity and motion?
• Were they able to perform and evaluate the experiment?
• Who struggled with applying formulas to vertical motion?