Grade 5 Science Force And Energy β Gravity Notes
Science Notes: Gravity
Topic: Force and Energy β Subtopic: Gravity (Age 10, Kenya)
Learning goals
- Know what gravity is.
- Understand how gravity acts on objects (makes things fall and gives weight).
- Try a simple classroom activity to see gravity at work.
What is gravity?
Gravity is a force that pulls objects towards each other. On Earth, gravity pulls things toward the ground. This is why when you drop a ball, it falls down.
Earth
π
β
Gravity pulls the apple down
Key ideas (simple)
- Gravity pulls things toward the ground.
- Gravity gives objects weight. Heavier objects feel a bigger pull.
- All objects fall at about the same rate if air does not get in the way.
Words to learn
- Gravity β the pull between objects (e.g., Earth and a ball).
- Mass β how much matter (stuff) is in an object. Measured in kilograms (kg).
- Weight β the force of gravity on an object. Measured in newtons (N).
- Free fall β when something falls under gravity alone (no other pushes).
A simple rule (formula)
Weight = mass Γ gravitational strength
W = m Γ g
where g on Earth β 9.8 N/kg (you can use g β 10 N/kg for easy sums)
W = m Γ g
where g on Earth β 9.8 N/kg (you can use g β 10 N/kg for easy sums)
Example: If a student has mass 30 kg, weight β 30 Γ 10 = 300 N (newtons).
Class activity 1 β Drop test (in school compound)
- Get two objects: a small stone and a pencil (or a small ball and a feather).
- Hold them at the same height and let go at the same time.
- Watch which lands first. If outdoors with wind, do the test indoors or hold hands close to the ground.
- Talk: Did both fall? Did one fall faster? Why might the feather fall slower (air resistance)?
Class activity 2 β Weighing with a spring scale (or simple balance)
- Use a spring scale or a balance to measure different objects (e.g., mango, stone, book).
- Record mass and the weight shown (if using spring scale).
- Notice: heavier mass means bigger pull from gravity (bigger weight).
Everyday examples in Kenya
- Why apples fall from a mango tree in the farm or school garden.
- Why we stay on the ground and donβt float away from Earth.
- Why water falls down when you pour from a jerry can.
Safety tips
- Drop objects carefully. Do not drop heavy stones near people.
- Use soft ground or a mat for experiments where things might bounce.
- Ask a teacher or adult for help with scales or higher experiments.
Quick quiz (try these)
- What does gravity do? (one short sentence)
- Which is the force that gives you weight?
- If mass = 5 kg and g = 10 N/kg, what is the weight? (show working)
- Why might a feather fall slower than a stone in air?
Summary
Gravity is the pull that brings objects to the ground. It gives objects weight. You can see gravity at work when things fall, when you jump and come back down, and when water flows down a hill.
Prepared for Kenyan learners (age ~10). Try the activities with a teacher or parent.