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Ionising and Non-ionising Radiation
Electromagnetic radiation can be described as ionising or non-ionising depending on whether individual photons have enough energy to remove electrons from atoms or molecules.
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Ionising and Non-ionising Radiation
Recommended for Class 10
Ionising and Non-ionising Radiation
Electromagnetic radiation can be described as ionising or non-ionising depending on whether individual photons have enough energy to remove electrons from atoms or molecules.
Non-ionising Radiation
Lower-frequency electromagnetic waves are generally non-ionising.
Examples include:
radio; microwaves; infrared; visible light.
Their photons generally do not have enough energy to ionise ordinary atoms directly.
Ionising Radiation
Higher-frequency radiation can be ionising.
Examples include:
higher-energy ultraviolet; X-rays; * gamma rays.
Ionising radiation can remove electrons and form ions.
Why It Matters
Ionisation can damage important biological molecules such as DNA.
This makes exposure control important.
Important Nuance
The exact dividing line is not simply a named colour boundary.
Photon energy matters:
**E = hf**
Ionising and Non-ionising Radiation — Advanced
Common Mistakes
Common Mistakes
- Mistake
Non-ionising does not mean completely harmless.
- Mistake
Microwaves and infrared can still cause heating at sufficient intensity.
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Practice
PQ
Q1. Define ionising radiation.
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Q2. Define non-ionising radiation.
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Q3. Give three examples of each.
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Q4. Explain the photon energy link.
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Q5. Explain why non-ionising can still be harmful.
Exam Practice
EQ
Q1. Differentiate ionising and non-ionising radiation.
EQ
Q2. Give three examples of each.
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Q3. Explain photon energy link.
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Q4. Explain biological risk.
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Q5. Correct the statement “non-ionising means harmless.”
School-standard facts for Matric and Intermediate. Original explanations — not copied from textbooks.