Grade 8 Science DLL: Newton's Laws of Motion
Newton's Laws of Motion
Learning Standards
Content Standard
Learners demonstrate understanding of Newton's three laws of motion and forces
Performance Standard
Learners shall be able to apply Newton's laws to analyze motion in everyday situations
Learning Competency
Understanding and applying Newton's three laws of motion
Code: S8FE-Ia-15
Complete Lesson Plan
Learning Objectives
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State and explain Newton's three laws of motion
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Identify real-world examples of each law
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Apply Newton's laws to explain everyday phenomena
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Solve simple problems involving force, mass, and acceleration
Lesson Procedures
motivation
Demonstration: The Tablecloth Trick (5 minutes)
Place a glass of water on a smooth tablecloth. Quickly pull the tablecloth.
Ask students:
- Why did the glass stay in place?
- What force acted on it?
This introduces the concept of inertia.
presentation
Explaining Newton's Three Laws (18 minutes)
First Law - Law of Inertia
- Objects resist changes in their state of motion
- Examples: Seatbelts in cars, dishes staying on a moving tablecloth
Second Law - F = ma
- The acceleration of an object depends on the force applied and its mass
- Formula: Force = mass × acceleration
- Examples: Pushing a shopping cart, kicking a soccer ball
Third Law - Action-Reaction
- Forces always come in pairs
- Examples: Swimming (pushing water backward moves you forward), rocket propulsion, walking
Demonstrate each law with simple experiments:
- Roll a toy car and stop it suddenly
- Push books of different masses with the same force
- Release an inflated balloon
generalization
Summary and Real-World Applications (5 minutes)
- Newton's laws explain how forces affect motion
- First Law: Objects maintain their state unless a force acts on them
- Second Law: Greater force or less mass = greater acceleration
- Third Law: All forces have equal and opposite reactions
- These laws apply to everything from sports to space travel
guided practice
Activity: Identifying the Laws (10 minutes)
Present scenarios and have students identify which law applies:
- A passenger lurches forward when a jeepney stops suddenly
- It's harder to push a loaded cart than an empty one
- A swimmer pushes water backward and moves forward
- A ball rolling on grass slows down and stops
- A rocket launches by expelling gases downward
Discuss each answer as a class.
independent practice
Problem Solving Activity (10 minutes)
Solve simple F = ma problems:
- If a 5 kg object is pushed with a force of 20 N, what is its acceleration?
- What force is needed to accelerate a 10 kg box at 3 m/s²?
Students work individually and check answers with a partner.
preliminary activities
Prayer and Greetings (2 minutes)
Attendance Check (1 minute)
Review of Previous Lesson (3 minutes) Recall the concepts of force and motion discussed in previous lessons.
Assessment
answers
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An object at rest stays at rest and an object in motion stays in motion with the same speed and direction unless acted upon by an unbalanced force (Law of Inertia)
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F = ma (Force equals mass times acceleration)
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Examples: Walking (foot pushes backward on ground, ground pushes forward on foot), swimming, rowing a boat, jumping, rocket launching
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a = F/m = 12 N / 4 kg = 3 m/s²
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Due to inertia (Newton's First Law), passengers tend to maintain their forward motion even when the vehicle stops, causing them to jerk forward until friction or seatbelts provide the stopping force
questions
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State Newton's First Law of Motion.
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What is the formula for Newton's Second Law?
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Give an example of Newton's Third Law from everyday life.
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Calculate the acceleration of a 4 kg object when a force of 12 N is applied.
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Why do passengers in a vehicle jerk forward when the vehicle stops suddenly?
Materials & Resources
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Toy car
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Stack of books (different masses)
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Tablecloth and glass
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Inflated balloon
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Ball
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Whiteboard and markers
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Calculator
remarks
Students were highly engaged during the demonstrations. Visual and hands-on activities helped reinforce abstract concepts. Some students needed additional practice with the mathematical applications of F = ma.
assignment
Homework Assignment:
- Find and describe 3 real-life examples of Newton's laws at home or in your community (one for each law)
- Solve the following problems:
- A 6 kg object requires a force of 18 N. What is its acceleration?
- What force is needed to accelerate a 15 kg object at 2 m/s²?
- Draw and label a diagram showing action-reaction force pairs for one of your examples
Write your answers in your science notebook.
subject matter
Topic: Newton's Laws of Motion
Key Concepts:
- First Law (Law of Inertia): An object at rest stays at rest, and an object in motion stays in motion unless acted upon by an unbalanced force
- Second Law (F = ma): Force equals mass times acceleration
- Third Law (Action-Reaction): For every action, there is an equal and opposite reaction
Reference Materials:
Science 8 Learner's Material, pp. 156-175
Materials Needed:
Toy car, books, balloon, string, ball