Activity 4.1: Finding Magnetic Materials
Goal: To identify which objects stick to a magnet.
- Procedure: Touch a magnet to various objects like a pencil, eraser, iron nail, and plastic scale.
- Observation: The magnet only sticks to the iron nail. It does not stick to wood, plastic, or rubber.
- Conclusion: Iron is a magnetic material. Wood, plastic, and rubber are non-magnetic.
Activity 4.2: Iron Filings Pattern
Goal: To find the strongest part of a magnet.
- Procedure: Spread iron filings on a paper and place a bar magnet on it. Tap the paper.
- Observation: The filings cling heavily to the two ends of the magnet. Very few stick to the center.
- Conclusion: Magnetic force is concentrated at the two poles.
Activity 4.3: Freely Suspended Magnet
Goal: To find directions.
- Procedure: Suspend a bar magnet freely with a thread. Rotate it and let it stop.
- Observation: It always stops in the North-South direction.
- Conclusion: Magnets have directional properties used for navigation.
Activity 4.4: Making a Compass
Goal: To create a DIY compass.
- Procedure: Magnetize a needle using the “single touch method” (rubbing one pole in one direction). Float it on a cork in water.
- Observation: The floating needle rotates and settles in the North-South direction.
- Conclusion: A magnetized needle acts like a compass.
Activity 4.5: Interaction of Magnets
Goal: To study attraction and repulsion.
- Procedure: Bring N-pole of one magnet near N-pole of another, then near S-pole.
- Observation:
- N-N Push away (Repel)
- N-S Pull together (Attract)
- Conclusion: Like poles repel; unlike poles attract.
Activity 4.7: Magnetic Force Through Materials
Goal: To see if magnetism works through barriers.
- Procedure: Place a piece of wood or plastic between a magnet and a compass/iron object.
- Observation: The compass needle still deflects; the iron object still moves.
- Conclusion: Magnetic force can pass through non-magnetic materials like wood, plastic, and glass.