P3 Physical Properties of Materials 🔬🧪
Created by Miss Clarissa Ng | www.clartutors.com
What Are Physical Properties?
- Materials can be classified by their physical properties, such as strength, flexibility, waterproof, ability to float or sink in water (buoyancy), and transparency.
- Objects around us are made of different materials — they are often obtained from the environment or created by humans from resources found in nature.
💪 Strength
- The strength of a material refers to its ability to withstand loads without breaking or tearing.
- Strong materials do not break or tear easily when pulled, pushed, dropped or knocked.
- Materials that are not strong (or weak) will break or tear easily when pulled, pushed, dropped or knocked.
- Strong materials can be used to make objects that need to support heavy loads, such as bridges, chairs and bags.
🤸 Flexibility
- The flexibility of a material refers to its ability to bend without breaking or tearing.
- Flexible materials bend easily without breaking.
- Materials that are not flexible (or rigid) do not bend easily or break when bent.
- More flexible materials bend more under the same force applied.
- Flexible materials can be used to make objects that wrap around our bodies, such as clothes, or objects that bend around corners, such as a hose.
💧 Waterproof (Absorbency)
- A material can be waterproof or not depending on its ability to absorb water or other liquids.
- Waterproof materials do not absorb water and do not allow water to pass through.
- Materials that are not waterproof (or absorbent) absorb water and allow water to pass through.
- Waterproof materials can be used to make objects that contain liquids or prevent the user from getting wet, such as bottles, raincoats, umbrellas, goggles and the roof of a tent.
- Materials that can absorb water are used to make objects that keep the user dry, such as towels, diapers and sportswear.
🚣 Ability to Float or Sink in Water
- The buoyancy of a material refers to its ability to float or sink in water or other liquids.
- Materials that float on water stay on or near the surface because they are less dense than water.
- Materials that sink in water are generally more dense than water.
🔦 Transparency
- The transparency of a material refers to the amount of light that can pass through it.
- Materials that allow most light to pass through are transparent — e.g. vehicle windshields, spectacle lenses.
- Materials that allow some light to pass through are translucent — e.g. sunglasses lenses.
- Materials that do not allow any light to pass through are opaque — e.g. bathroom doors (for privacy).
🧱 Common Materials & Their Properties
Wood, metal, ceramic, rubber, glass, plastic and fabric are commonly used to make objects.
🪵 Wood
- Obtained from trees
- Strong, not flexible
- Floats on water
- Does not allow any light to pass through
⚙️ Metal
- Obtained from the ground
- Strong, not flexible
- Waterproof, sinks in water
- Does not allow any light to pass through
🏺 Ceramic
- Made by heating clay from the ground
- Breaks easily when dropped, not flexible
- Does not allow any light to pass through
🎈 Rubber
- Obtained from rubber tree sap
- Strong, flexible, waterproof
- Does not allow any light to pass through
🥛 Glass
- Made from heating sand
- Breaks easily, not flexible
- Waterproof, sinks in water
- May allow most or some light to pass through
🧴 Plastic
- Made from petroleum underground
- Does not break easily, flexible
- Waterproof, generally floats on water
- May allow most, some or no light to pass through
🧵 Fabric
- From animals (leather, wool, silk) or plants (cotton)
- Flexible, absorbs water
🎯 Choosing the Most Suitable Material
We choose materials based on their properties to match the function of the object.
Set-up 1: Which material is best for making a bag?
| Step | Answer |
|---|---|
| Material chosen | Material X |
| Results | It could hold the most weights without breaking |
| Property shown | It is the strongest material |
| Function of object | A bag needs to carry heavy loads without breaking or tearing |
Set-up 2: Which material is best for a raincoat? A towel?
| Step | Raincoat → Material Y | Towel → Material X |
|---|---|---|
| Results | All water collected on top — did not absorb any water | All water was absorbed by the material |
| Property shown | Waterproof material | Absorbs the most water |
| Function of object | A raincoat needs to keep the user dry in the rain | A towel needs to dry the user |
💡 Exam Tip: Remember the 5 Properties
Memorise the 5 properties of materials using S-T-A-F-F:
- S — Strength
- T — Transparency
- A — Absorbency
- F — Flexibility
- F — Float on water? (Buoyancy)
📋 Summary of Properties
| Property | Definition |
|---|---|
| Strength | Ability to withstand heavy loads without breaking or tearing |
| Transparency |
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| Absorbency |
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| Flexibility |
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| Float on water? (Buoyancy) |
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