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.

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❌ 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.

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⚠️ 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.

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🎯 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.

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👀 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.

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❌ 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.

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⚠️ 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.

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🎯 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.

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👀 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.

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❌ 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.

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⚠️ 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.

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🎯 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.

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📌 Arus daripada sumber dibahagikan kepada beberapa cabang.

📌 Current from the source is divided among the branches.

I = I₁ + I₂ + I₃

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📌 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.

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🔍 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.