Physical Sciences – DBE 2025 MayJune – Question 10.1 – Matter and Materials

The Question

Details

💡 Hint

When defining a key term like ‘work function,’ remember to specify both the ‘minimum’ aspect and the ‘action’ it enables for electrons on a metal surface.

📝 Solution Steps

1. Step 1: Recall the definition of work function from your notes or textbook.
2. Step 2: Ensure your definition includes the idea of ‘minimum energy’.
3. Step 3: Specify what this energy allows (ejecting electrons) and from where (a metal surface).

📚 Explanation

The work function (W₀) of a metal is a fundamental concept in the photoelectric effect. It represents the minimum amount of energy that an electron needs to absorb to escape from the surface of that specific metal. Think of it as an ‘energy barrier’ that electrons must overcome to be emitted. This energy is characteristic of the material itself.

✅ Answer

The minimum energy (of incident photons) that can eject electrons from a metal/surface.

⚠️ Common Mistakes

• Omitting ‘minimum’ from the definition, implying any energy is sufficient.
• Not specifying ‘from the surface of a metal’, making the definition too general.