GW Instek GPC-3030 Analog DC Power Supply

• Triple Output
• 5V, 3A Fixed output

 

British Optical Lens Co-Bi-Concave lens

 

SPM Physics Amali: Resistance Depends on Material

 

Constantant swg 28 vs Nichrome swg 28 vs Cooper swg 28

Nichrome, a non-magnetic 80/20 alloy of nickel and chromium, is the most common resistance wire for heating purposes because it has a high resistivity and resistance to oxidation at high temperatures.

🧵 Does the Type of Wire Affect Resistance?

Rintangan dawai bergantung pada jenis bahan yang digunakan. Bahan yang berbeza mempunyai kerintangan tentu (ρ) yang berbeza.

The resistance of a wire depends on the material used. Different materials have different resistivities (ρ).

---

👀 Key Observations | Pemerhatian Penting

✅ Semua dawai mempunyai saiz yang hampir sama (SWG 28).

✅ All wires have approximately the same diameter (SWG 28).

✅ Panjang dawai yang digunakan adalah sama.

✅ The wires used have the same length.

✅ Bacaan arus berbeza apabila bahan dawai ditukar.

✅ The current reading changes when the wire material is changed.

✅ Ini menunjukkan setiap bahan mempunyai rintangan yang berbeza.

✅ This shows that different materials have different resistance values.

---

❌ Common Mistakes

❌ Menganggap semua dawai mempunyai rintangan yang sama.

❌ Assuming all wires have the same resistance.

❌ Mengelirukan rintangan (R) dengan kerintangan tentu (ρ).

❌ Confusing resistance (R) with resistivity (ρ).

❌ Tidak mengawal panjang dan diameter dawai semasa membuat perbandingan.

❌ Failing to keep wire length and diameter constant during comparison.

---

⚠️ Safety / Handling

⚠️ Matikan bekalan kuasa selepas mengambil bacaan.

⚠️ Switch off the power supply after taking readings.

⚠️ Dawai rintangan boleh menjadi panas apabila arus mengalir terlalu lama.

⚠️ Resistance wires may become hot if current flows for a long period.

⚠️ Elakkan menyentuh bahagian dawai yang panas.

⚠️ Avoid touching heated sections of the wire.

---

🎯 SPM Exam Tip

📌 Untuk dawai yang mempunyai panjang dan diameter yang sama:

📌 For wires with the same length and diameter:

Copper → Lowest Resistance

Constantan → Higher Resistance

Nichrome → Highest Resistance

📌 Tembaga membenarkan arus mengalir dengan lebih mudah.

📌 Copper allows current to flow more easily.

📌 Nichrome mempunyai kerintangan tentu yang tinggi.

📌 Nichrome has a high resistivity.

📌 Sebab itu nichrome digunakan dalam elemen pemanas.

📌 That is why nichrome is commonly used in heating elements.

---

🧠 SPM Concept Check

Formula yang perlu diingati:

Formula to remember:

R = ρL/A

di mana / where:

• R = Resistance
• ρ = Resistivity
• L = Length of wire
• A = Cross-sectional area

📌 Jika panjang dan diameter adalah tetap, rintangan bergantung kepada nilai ρ (resistivity).

📌 If length and diameter are fixed, resistance depends on ρ (resistivity).

A MODEL TRANSFORMER

Working Principle of A Transformer

• A transformer consists of a primary coil and a secondary coil wound on a soft iron core.
• When an alternating current flows in the primary coil, a changing magnetic flux is generated around the primary coil.
• The changing magnetic flux is transferred to the secondary coil through the iron core.
• The changing magnetic flux is cut by the secondary coil, hence induces an e.m.f. in the secondary coil.
• The magnitude of the output voltage can be controlled by the ratio of the number of primary coil and secondary coil.

 

⚡ Short Circuit (Litar Pintas)

 

What Is It? | Apakah Itu?

Litar pintas berlaku apabila arus elektrik mengalir melalui laluan yang mempunyai rintangan sangat rendah sehingga memintas komponen yang sepatutnya dilalui.

A short circuit occurs when electric current flows through a path with very low resistance, bypassing the intended component.

---

👀 How to Identify | Cara Mengenal Pasti

✅ Sebuah komponen (contohnya mentol) dipintas oleh wayar.

✅ A component (e.g. a bulb) is bypassed by a wire.

✅ Arus memilih laluan dengan rintangan paling rendah.

✅ Current chooses the path of least resistance.

✅ Komponen yang dipintas biasanya tidak berfungsi.

✅ The bypassed component usually does not operate.

---

❌ Common Mistakes

❌ Menyangka kedua-dua mentol masih berada dalam litar.

❌ Assuming both bulbs remain in the circuit.

❌ Tidak menyedari wayar telah memintas mentol.

❌ Failing to notice that the wire bypasses the bulb.

❌ Menghasilkan sambungan litar yang salah semasa eksperimen.

❌ Creating incorrect circuit connections during an experiment.

---

⚠️ Safety Alert

⚠️ Litar pintas boleh menyebabkan arus yang sangat besar.

⚠️ A short circuit can cause a very large current.

⚠️ Wayar dan bekalan kuasa boleh menjadi panas.

⚠️ Wires and power supplies may become hot.

⚠️ Matikan bekalan kuasa dengan segera jika berlaku litar pintas.

⚠️ Switch off the power supply immediately if a short circuit occurs.

---

🎯 SPM Exam Tip

📌 Mentol yang dipintas oleh wayar tidak akan menyala.

📌 A bulb bypassed by a wire will not light up.

📌 Arus lebih suka mengalir melalui wayar kerana rintangannya jauh lebih rendah daripada mentol.

📌 Current prefers flowing through the wire because its resistance is much lower than that of the bulb.

Audio Signal Generator AG-202A

Country: Japan

Manufacturer / Brand: Kenwood, Trio-Kenwood Inc.; Komagane

Year: 1970 ??

 

Diffraction Grating

To produce a bright and sharp interference pattern for light, a diffraction grating is used in preference to a Young's double slit.

A diffraction grating consists of many equally-spaced slits placed extremely close together, e.g., 300 lines/mm.

 

Plug Key: Function, Common Mistakes & SPM Physics Amali Tips

👀 Cara Membaca | Reading Technique

✅ Pastikan plug dimasukkan sepenuhnya sebelum mengambil bacaan.

✅ Ensure the plug is fully inserted before taking any reading.

✅ Semak bahawa litar lengkap dan meter menunjukkan bacaan yang stabil.

✅ Check that the circuit is complete and the meter shows a stable reading.

✅ Ambil bacaan hanya selepas semua sambungan dibuat dengan betul.

✅ Record readings only after all connections are properly secured.

---

❌ Common Mistakes

❌ Plug tidak dimasukkan sepenuhnya menyebabkan litar tidak lengkap.

❌ The plug is not fully inserted, resulting in an incomplete circuit.

❌ Menganggap litar masih lengkap selepas plug ditanggalkan.

❌ Assuming the circuit remains complete after the plug is removed.

❌ Sambungan wayar yang longgar pada terminal.

❌ Loose wire connections at the terminals.

---

⚠️ Safety / Handling

⚠️ Matikan bekalan kuasa sebelum memasukkan atau menanggalkan plug jika perlu mengubah sambungan litar.

⚠️ Switch off the power supply before inserting or removing the plug when modifying circuit connections.

⚠️ Pastikan terminal bersih dan bebas daripada kakisan.

⚠️ Ensure the terminals are clean and free from corrosion.

⚠️ Elakkan menarik wayar secara kasar semasa mengendalikan plug key.

⚠️ Avoid pulling the wires forcefully when handling the plug key.

---

🎯 SPM Exam Tip

📌 Plug key biasanya digunakan untuk mengawal aliran arus semasa eksperimen dijalankan.

📌 A plug key is commonly used to control the flow of current during an experiment.

📌 Apabila plug dimasukkan, litar lengkap dan arus mengalir.

📌 When the plug is inserted, the circuit is complete and current flows.

📌 Apabila plug ditanggalkan, litar terbuka dan arus terhenti.

📌 When the plug is removed, the circuit becomes open and current stops flowing.

 

SPM Physics Amali: How to Identify a Series Circuit

Litar siri terdiri daripada komponen yang disambungkan dalam satu laluan sahaja. Arus yang sama mengalir melalui setiap komponen dalam litar.

A series circuit consists of components connected in a single path. The same current flows through every component in the circuit.

---

👀 Key Observations | Pemerhatian Penting

✅ Semua komponen disambungkan dalam satu laluan yang berterusan.

✅ All components are connected in a single continuous path.

✅ Arus yang sama mengalir melalui setiap mentol.

✅ The same current flows through every bulb.

✅ Kedua-dua mentol biasanya lebih malap berbanding satu mentol sahaja.

✅ Both bulbs are usually dimmer compared to a single bulb.

---

❌ Common Mistakes

❌ Menganggap voltan adalah sama pada setiap mentol.

❌ Assuming the voltage is the same across every bulb.

❌ Mengelirukan litar siri dengan litar selari.

❌ Confusing a series circuit with a parallel circuit.

❌ Sambungan wayar yang longgar menyebabkan litar terbuka.

❌ Loose wire connections causing an open circuit.

---

⚠️ What Happens If One Bulb Fails?

⚠️ Jika satu mentol terbakar atau ditanggalkan, keseluruhan litar akan terputus.

⚠️ If one bulb burns out or is removed, the entire circuit is broken.

⚠️ Semua mentol lain akan padam.

⚠️ All other bulbs will go out.

---

🎯 SPM Exam Tip

📌 Dalam litar siri:

📌 In a series circuit:

• ✅ Current is the same throughout the circuit.

• ✅ Arus adalah sama di semua bahagian litar.

• ✅ Total resistance increases when more bulbs are added.

• ✅ Jumlah rintangan bertambah apabila lebih banyak mentol ditambah.

• ✅ Bulb brightness decreases when more bulbs are connected.

• ✅ Kecerahan mentol berkurang apabila lebih banyak mentol disambungkan.

How is the voltmeter and ammeter connected in a circuit?

A voltmeter is connected in parallel with a device to measure its voltage, while an ammeter is connected in series with a device to measure its current.

 

 

SPM Physics Amali: Understanding Parallel Circuits

 

Light bulbs in parallel

💡 Light Bulbs in a Parallel Circuit (Litar Selari)

Litar selari terdiri daripada dua atau lebih cabang yang disambungkan merentasi bekalan kuasa yang sama. Setiap cabang menerima voltan bekalan yang penuh.

A parallel circuit consists of two or more branches connected across the same power supply. Each branch receives the full supply voltage.

---

👀 Key Observations | Pemerhatian Penting

✅ Terdapat lebih daripada satu laluan untuk arus mengalir.

✅ There is more than one path for current to flow.

✅ Setiap mentol menerima voltan yang sama dengan sumber kuasa.

✅ Each bulb receives the same voltage as the power supply.

✅ Kedua-dua mentol menyala dengan lebih terang berbanding dalam litar siri.

✅ Both bulbs shine brighter compared to a series circuit.

✅ Jika satu mentol ditanggalkan, mentol yang lain masih menyala.

✅ If one bulb is removed, the other bulb remains lit.

---

❌ Common Mistakes

❌ Menganggap arus adalah sama dalam setiap cabang.

❌ Assuming the current is the same in every branch.

❌ Mengelirukan litar selari dengan litar siri.

❌ Confusing a parallel circuit with a series circuit.

❌ Menyangka semua mentol akan padam apabila satu mentol rosak.

❌ Assuming all bulbs will go out when one bulb fails.

---

⚠️ Safety / Handling

⚠️ Pastikan setiap cabang disambungkan dengan betul pada terminal bekalan kuasa.

⚠️ Ensure each branch is connected correctly to the power supply terminals.

⚠️ Elakkan sambungan wayar yang longgar kerana boleh menyebabkan bacaan tidak stabil.

⚠️ Avoid loose wire connections as they may cause unstable readings.

⚠️ Matikan bekalan kuasa sebelum mengubah susunan litar.

⚠️ Switch off the power supply before modifying the circuit.

---

🎯 SPM Exam Tip

📌 Dalam litar selari:

📌 In a parallel circuit:

V₁ = V₂ = V₃

✅ Voltan adalah sama pada setiap cabang.

✅ Voltage is the same across every branch.

---

📌 Arus daripada sumber dibahagikan kepada beberapa cabang.

📌 Current from the source is divided among the branches.

I = I₁ + I₂ + I₃

---

📌 Jika satu mentol ditanggalkan, cabang lain masih lengkap.

📌 If one bulb is removed, the other branches remain complete.

📌 Sebab itu lampu rumah disambung secara selari.

📌 That is why household lighting circuits are connected in parallel.

---

🔍 How to Identify a Parallel Circuit Quickly

✅ Mempunyai cabang atau simpang wayar.

✅ Has branches or junctions.

✅ Terdapat lebih daripada satu laluan arus.

✅ More than one path for current flow.

✅ Komponen boleh berfungsi secara bebas.

✅ Components can operate independently.

✅ Satu mentol rosak tidak menjejaskan mentol yang lain.

✅ One failed bulb does not affect the others.

SPM Physics Amali: Electromagnetic Induction Explained

 

Electromagnetic Induction (Induced Current)

Apabila magnet bergerak relatif terhadap gegelung, arus teraruh dihasilkan dalam gegelung.

When a magnet moves relative to a coil, a current is induced in the coil.

---

👀 Key Observations | Pemerhatian Penting

✅ Jarum galvanometer terpesong apabila magnet digerakkan masuk ke dalam gegelung.

✅ The galvanometer needle deflects when the magnet is moved into the coil.

✅ Jarum juga terpesong apabila magnet ditarik keluar dari gegelung.

✅ The needle also deflects when the magnet is pulled out of the coil.

✅ Tiada pesongan apabila magnet dan gegelung berada dalam keadaan pegun.

✅ No deflection occurs when both the magnet and coil remain stationary.

✅ Pesongan berlaku hanya apabila terdapat perubahan fluks magnet.

✅ Deflection occurs only when there is a change in magnetic flux.

---

🔬 Physics Behind It | Prinsip Fizik

✅ Magnet yang bergerak menghasilkan perubahan medan magnet dalam gegelung.

✅ A moving magnet causes a changing magnetic field through the coil.

✅ Perubahan medan magnet menghasilkan arus teraruh.

✅ The changing magnetic field induces a current.

✅ Semakin cepat magnet digerakkan, semakin besar arus teraruh.

✅ The faster the magnet moves, the greater the induced current.

---

❌ Common Mistakes

❌ Menganggap magnet perlu menyentuh gegelung untuk menghasilkan arus.

❌ Assuming the magnet must touch the coil to induce a current.

❌ Menganggap magnet pegun boleh menghasilkan arus teraruh.

❌ Assuming a stationary magnet can induce current.

❌ Mengelirukan elektromagnet dengan induksi elektromagnet.

❌ Confusing an electromagnet with electromagnetic induction.

❌ Tidak memerhatikan arah pesongan galvanometer.

❌ Ignoring the direction of galvanometer deflection.

---

⚠️ Safety / Handling

⚠️ Gerakkan magnet secara perlahan dan terkawal.

⚠️ Move the magnet in a controlled manner.

⚠️ Elakkan menjatuhkan magnet atau galvanometer.

⚠️ Avoid dropping the magnet or galvanometer.

⚠️ Jangan menarik wayar sambungan dengan kuat.

⚠️ Do not pull the connecting wires forcefully.

---

🎯 SPM Exam Tip

📌 Arus teraruh hanya wujud apabila terdapat perubahan fluks magnet.

📌 Induced current exists only when there is a change in magnetic flux.

📌 Semakin laju magnet digerakkan:

📌 The faster the magnet is moved:

✅ Semakin besar pesongan galvanometer.

✅ The greater the galvanometer deflection.

---

📌 Menukar arah pergerakan magnet akan menukar arah arus teraruh.

📌 Reversing the direction of magnet movement reverses the induced current.

📌 Menukar kutub magnet yang memasuki gegelung juga menukar arah arus.

📌 Reversing the magnet pole entering the coil also reverses the induced current.

---

🧠 SPM Concept Check

Observation

Jarum galvanometer terpesong apabila magnet digerakkan.

The galvanometer needle deflects when the magnet is moved.

Inference

Arus teraruh dihasilkan dalam gegelung.

An induced current is produced in the coil.

Conclusion

Perubahan medan magnet menghasilkan arus teraruh.

A changing magnetic field induces an electric current.

SPM Physics Amali: Current Flow in a Series Circuit

Litar siri hanya mempunyai satu laluan untuk arus mengalir. Oleh itu, arus adalah sama di setiap bahagian litar.

A series circuit has only one path for current flow. Therefore, the current is the same at every point in the circuit.

---

👀 Key Observations | Pemerhatian Penting

✅ Ammeter menunjukkan bacaan yang sama walaupun diletakkan pada kedudukan yang berbeza dalam litar.

✅ The ammeter shows the same reading even when placed at different positions in the circuit.

✅ Hanya terdapat satu laluan untuk arus mengalir.

✅ There is only one path for current flow.

✅ Semua elektron mesti melalui setiap komponen dalam laluan yang sama.

✅ All electrons must pass through every component along the same path.

---

❌ Common Mistakes

❌ Menganggap arus semakin berkurang selepas melalui mentol.

❌ Assuming the current decreases after passing through a bulb.

❌ Menganggap bacaan ammeter bergantung pada kedudukan ammeter dalam litar siri.

❌ Assuming the ammeter reading depends on its position in a series circuit.

❌ Mengelirukan litar siri dengan litar selari.

❌ Confusing a series circuit with a parallel circuit.

---

⚠️ Safety / Handling

⚠️ Ammeter mesti disambung secara siri dengan litar.

⚠️ An ammeter must be connected in series with the circuit.

⚠️ Pastikan sambungan wayar kemas sebelum menghidupkan bekalan kuasa.

⚠️ Ensure all wire connections are secure before switching on the power supply.

⚠️ Matikan bekalan kuasa sebelum menukar kedudukan ammeter.

⚠️ Switch off the power supply before changing the ammeter position.

---

🎯 SPM Exam Tip

📌 Dalam litar siri:

📌 In a series circuit:

I₁ = I₂ = I₃

✅ Arus adalah sama pada semua bahagian litar.

✅ Current is the same throughout the circuit.

📌 Jika ammeter dipindahkan ke mana-mana kedudukan dalam litar siri, bacaannya tetap sama.

📌 If the ammeter is moved to any position in a series circuit, the reading remains the same.

📌 Ini kerana hanya terdapat satu laluan untuk aliran cas.

📌 This is because there is only one path for charge flow.

Magnetic field lines around a straight conductor carrying current.

 

A magnetic compass shows the presence and direction of the magnetic field around a straight length of current-carrying wire.

The field direction can also be determined using The Right-Hand Grip Rule.

Griffin & George Limited-Slit Plate for Griffin Raybox

 

Polaroid filter or Polariser

A Polaroid is artificially prepared thin, large sheet of crystalline polarizing material capable of producing plane polarized light. 

 

Griffin & George Limited -Steel Springs

 

Copper Rod and Brass Rod

 

Brass Rod 黄铜棒

Solid brass rods are strong pieces of brass that can be cut to a specific length and diameter for use in applications where corrosion resistance and electrical conductivity are both important. Comes in a variety of lengths and sizes and can be used for many different fittings and fasteners.

Copper Rod

Copper rod is used as raw material for the manufacturing of electric wire and cables and is produced by either our continuous casting or our oxygen-free continuous up-casting mills.

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.

---

👀 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.

---

❌ 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.

---

⚠️ 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.

---

🎯 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)

---

📌 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.

---

🖐️ 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

 

Enamelled Copper Wire (Magnet Wire)

Enamelled Copper Wire (Magnet Wire) is an insulated copper (or aluminium) electrical conductor used in motors, transformers and other electromagnetic equipment. When wound into a coil and energized, magnet wire creates an electromagnetic field.

DIY Ripple tank

Cara mudah untuk membuat tangki riak anda sendiri di rumah.

 

Pezon & Michel- Resistant invisible nylon thread

P et M was founded in Amboise, near Paris, after the end of 1st World War.

 

Griffin & George Limited - Bare Copper Wire 32 swg 50g

 

SPM Physics Amali: Why Is an Iron Core Laminated?

🧲 Laminated C-Shape Iron Core

A laminated C-shape iron core is used to concentrate and strengthen magnetic fields in devices such as transformers, electromagnets and induction experiments.

Teras besi berbentuk C berlamina digunakan untuk menumpukan dan menguatkan medan magnet dalam alat seperti transformer, elektromagnet dan eksperimen induksi.

---

👀 Cara Membaca | Reading Technique

✅ Perhatikan lapisan-lapisan nipis (laminations) yang membentuk teras besi.

✅ Observe the thin layered sheets (laminations) that form the iron core.

✅ Kenal pasti bentuk "C" yang membolehkan gegelung dipasang pada teras.

✅ Identify the "C" shape that allows coils to be mounted on the core.

✅ Semasa eksperimen, perhatikan perubahan kekuatan medan magnet apabila teras digunakan.

✅ During experiments, observe the increase in magnetic field strength when the core is used.

---

❌ Common Mistakes

❌ Menganggap teras besi pepejal lebih baik daripada teras berlamina.

❌ Assuming a solid iron core is better than a laminated iron core.

❌ Tidak menyedari bahawa lapisan-lapisan nipis digunakan untuk mengurangkan arus pusar (eddy currents).

❌ Failing to recognise that lamination reduces eddy currents.

❌ Mengelirukan iron core dengan magnet kekal.

❌ Confusing an iron core with a permanent magnet.

---

⚠️ Safety / Handling

⚠️ Handle with care as the iron core is heavy and can chip if dropped.

⚠️ Kendalikan dengan berhati-hati kerana teras besi agak berat dan boleh rosak jika terjatuh.

⚠️ Keep the surface free from rust and excessive moisture.

⚠️ Pastikan permukaan bebas daripada karat dan kelembapan berlebihan.

⚠️ Avoid strong impacts that may separate the laminated layers.

⚠️ Elakkan hentakan kuat yang boleh menyebabkan lapisan lamina tertanggal.

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🎯 SPM Exam Tip

📌 Laminations help to reduce eddy currents and minimise energy loss as heat.

📌 Lapisan lamina membantu mengurangkan arus pusar (eddy currents) dan kehilangan tenaga sebagai haba.

📌 Soft iron is used because it can be magnetised and demagnetised easily.

📌 Besi lembut digunakan kerana mudah dimagnetkan dan dinyahmagnetkan.

📌 Iron cores are commonly found in transformers, electromagnets and induction experiments.

📌 Teras besi biasanya digunakan dalam transformer, elektromagnet dan eksperimen induksi elektromagnet.

📌 If asked in SPM: "Why is the iron core laminated?" → ✅ To reduce eddy currents and energy loss.

📌 Jika ditanya dalam SPM: "Mengapa teras besi dilamina?" → ✅ Untuk mengurangkan arus pusar dan kehilangan tenaga.

 

SPM Physics Amali: Understanding Nichrome Wire (SWG 28)

 

🧵 Nichrome Wire (SWG 28)

Dawai nichrome ialah dawai rintangan yang diperbuat daripada aloi nikel dan kromium. Ia sering digunakan dalam eksperimen Fizik untuk mengkaji hubungan antara rintangan, panjang dawai, arus dan beza keupayaan.

Nichrome wire is a resistance wire made from an alloy of nickel and chromium. It is commonly used in Physics experiments to investigate the relationship between resistance, length, current and potential difference.

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👀 Cara Membaca | Reading Technique

✅ Ukur panjang dawai yang digunakan dengan pembaris atau metre rule dengan tepat.

✅ Measure the length of wire used accurately with a ruler or metre rule.

✅ Pastikan panjang dawai direkod dari titik sambungan ke kedudukan jockey atau klip.

✅ Ensure the wire length is measured from the terminal connection to the jockey or clip position.

✅ Ambil bacaan ammeter dan voltmeter hanya selepas bacaan menjadi stabil.

✅ Record ammeter and voltmeter readings only after they have stabilised.

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❌ Common Mistakes

❌ Mengukur panjang dawai dari titik yang salah.

❌ Measuring the wire length from the wrong reference point.

❌ Dawai tidak ditegangkan menyebabkan panjang sebenar berubah.

❌ The wire is not properly stretched, causing inaccurate length measurements.

❌ Menggunakan dawai yang telah menjadi panas semasa mengambil bacaan.

❌ Taking readings when the wire has already become hot.

❌ Mengelirukan nichrome wire dengan connecting wire biasa.

❌ Confusing nichrome wire with an ordinary connecting wire.

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⚠️ Safety / Handling

⚠️ Matikan bekalan kuasa apabila tidak mengambil bacaan.

⚠️ Switch off the power supply when readings are not being taken.

⚠️ Nichrome wire boleh menjadi panas selepas arus mengalir untuk tempoh yang lama.

⚠️ Nichrome wire may become hot after prolonged current flow.

⚠️ Elakkan menyentuh bahagian dawai yang panas dengan tangan.

⚠️ Avoid touching the heated section of the wire.

⚠️ Jangan menarik dawai terlalu kuat kerana ia mudah berubah bentuk.

⚠️ Do not stretch the wire excessively as it may deform.

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🎯 SPM Exam Tip

📌 Semakin panjang dawai nichrome, semakin besar rintangannya.

📌 The longer the nichrome wire, the greater its resistance.

📌 Apabila panjang dawai bertambah, bacaan ammeter biasanya berkurang.

📌 As the wire length increases, the ammeter reading usually decreases.

📌 Nichrome wire sering digunakan dalam eksperimen menentukan hubungan antara R ∝ l (resistance is proportional to length).

📌 Nichrome wire is commonly used in experiments investigating R ∝ l (resistance is proportional to length).

📌 Dalam SPM, jangan lupa nyatakan bahawa nichrome wire ialah resistance wire.

📌 In SPM answers, do not forget to state that nichrome wire is a resistance wire.

SPM Physics Amali: Understanding Young's Double Slit 1 mm dan 0.5mm

 Dwi celah Young digunakan untuk menunjukkan interferens gelombang cahaya dan menghasilkan corak jalur terang dan gelap pada skrin.

Young's double slit is used to demonstrate interference of light waves and produce a pattern of bright and dark fringes on a screen.

👀 Cara Membaca | Reading Technique

✅ Pastikan dwi celah berada tegak dan sejajar dengan sumber cahaya laser.

✅ Ensure the double slit is upright and aligned with the laser light source.

✅ Perhatikan corak jalur terang dan gelap yang terbentuk pada skrin.

✅ Observe the pattern of bright and dark fringes formed on the screen.

✅ Ukur jarak antara beberapa jalur terang untuk mendapatkan nilai purata yang lebih tepat.

✅ Measure the distance across several bright fringes and calculate the average for greater accuracy.

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❌ Common Mistakes

❌ Mengelirukan ukuran pemisahan celah (0.5 mm atau 1.0 mm).

❌ Confusing the slit separation (0.5 mm or 1.0 mm).

❌ Dwi celah tidak sejajar dengan laser menyebabkan corak interferens kabur.

❌ Misaligning the double slit with the laser, resulting in unclear fringes.

❌ Mengukur hanya satu jalur terang yang menyebabkan ralat lebih besar.

❌ Measuring only one fringe, leading to larger experimental errors.

❌ Menyangka jalur terang terhasil daripada pembiasan, bukan interferens.

❌ Assuming bright fringes are caused by refraction instead of interference.

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⚠️ Safety / Handling

⚠️ Pegang bingkai slaid dan elakkan menyentuh bahagian celah yang halus.

⚠️ Hold the frame and avoid touching the delicate slit area.

⚠️ Pastikan slaid tidak tercalar kerana boleh menjejaskan corak interferens.

⚠️ Ensure the slide is not scratched as it may affect the interference pattern.

⚠️ Jika menggunakan laser, jangan halakan pancaran ke arah mata.

⚠️ When using a laser, never direct the beam into anyone's eyes.

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🎯 SPM Exam Tip

📌 Celah yang lebih kecil jaraknya menghasilkan jalur interferens yang lebih berjauhan.

📌 A smaller slit separation produces fringes that are further apart.

📌 Celah 0.5 mm menghasilkan jarak jalur yang lebih besar berbanding celah 1.0 mm.

📌 A 0.5 mm slit separation produces wider fringe spacing than a 1.0 mm separation.

📌 Formula yang sering digunakan:

📌 Commonly used formula:

x = λD / a

di mana:

where:

• x = fringe spacing
• λ = wavelength
• D = distance from slit to screen
• a = slit separation

📌 Apabila a berkurang, nilai x bertambah.

📌 When a decreases, the fringe spacing x increases.