Simple D.C. Motor Kit: Motor Effect, Common Mistakes & SPM Physics Amali Tips

A simple D.C. motor converts electrical energy into mechanical energy. It works based on the interaction between a magnetic field and a current-carrying coil.

Motor arus terus (D.C.) ringkas menukarkan tenaga elektrik kepada tenaga mekanik. Ia berfungsi melalui interaksi antara medan magnet dan gegelung yang membawa arus.

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👀 Key Observations | Pemerhatian Penting

✅ Apabila arus mengalir dalam gegelung, gegelung mula berputar.

✅ When current flows through the coil, the coil starts to rotate.

✅ Gegelung berada di antara kutub Utara (N) dan Selatan (S) magnet.

✅ The coil is placed between the North (N) and South (S) poles of the magnet.

✅ Arah putaran bergantung pada arah arus dan arah medan magnet.

✅ The direction of rotation depends on the current direction and magnetic field direction.

✅ Putaran berterusan dihasilkan oleh komutator (split-ring commutator).

✅ Continuous rotation is achieved by the split-ring commutator.

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❌ Common Mistakes

❌ Menganggap magnet sahaja menyebabkan gegelung berputar.

❌ Assuming the magnet alone causes the coil to rotate.

❌ Terlupa bahawa arus mesti mengalir dalam gegelung.

❌ Forgetting that current must flow through the coil.

❌ Mengelirukan fungsi komutator dengan berus karbon (carbon brushes).

❌ Confusing the function of the commutator with the carbon brushes.

❌ Menganggap gegelung boleh berputar berterusan tanpa pembalikan arus.

❌ Assuming the coil can rotate continuously without current reversal.

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⚠️ Safety / Handling

⚠️ Pastikan voltan bekalan tidak terlalu tinggi.

⚠️ Ensure the supply voltage is not too high.

⚠️ Elakkan menyentuh gegelung ketika motor sedang berputar.

⚠️ Avoid touching the coil while the motor is rotating.

⚠️ Matikan bekalan kuasa sebelum melaraskan kedudukan magnet atau gegelung.

⚠️ Switch off the power supply before adjusting the magnet or coil position.

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🎯 SPM Exam Tip

📌 Komponen utama motor D.C.:

📌 Main components of a D.C. motor:

✅ Magnet Permanen (Permanent Magnet)

✅ Gegelung Dawai (Coil)

✅ Komutator Gelang Belah (Split-Ring Commutator)

✅ Berus Karbon (Carbon Brushes)

✅ Bekalan Arus Terus (D.C. Supply)

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📌 Fungsi komutator:

📌 Function of the commutator:

✅ Menukarkan arah arus setiap setengah pusingan.

✅ Reverses the current every half rotation.

✅ Memastikan putaran berlaku dalam arah yang sama secara berterusan.

✅ Ensures continuous rotation in the same direction.

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🖐️ Fleming's Left-Hand Rule

Digunakan untuk menentukan arah daya ke atas gegelung.

Used to determine the direction of force acting on the coil.

✅ Thumb = Force / Motion
✅ Ibu Jari = Daya / Pergerakan

✅ First Finger = Magnetic Field
✅ Jari Telunjuk = Medan Magnet

✅ Second Finger = Current
✅ Jari Hantu = Arus