In Rutherford's alpha-rays scattering experiment, the alpha particles are detected using a screen coated with

Options

A. Copper sulphide
B. Zinc sulphide
C. Graphite
D. Gold

Answer

To solve the question regarding the detection of alpha particles in Rutherford's alpha-ray scattering experiment, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding the Experiment**: Rutherford's alpha-ray scattering experiment was designed to probe the structure of the atom by observing how alpha particles interact with a thin foil of gold.

2. **Detection Method**: In this experiment, alpha particles are emitted and directed towards a target. To detect these particles after they interact with the target, a detection screen is required.

3. **Material Used for Detection**: The screen used for detecting alpha particles is crucial. It needs to be sensitive enough to register the impact of the alpha particles.

4. **Identifying the Coating**: The correct material that was used to coat the detection screen in Rutherford's experiment is zinc sulfide (ZnS). When alpha particles strike the zinc sulfide screen, they produce flashes of light (scintillations).

5. **Conclusion**: Based on the information about the detection method and the materials used, we conclude that the screen is coated with zinc sulfide.

### Final Answer:
The alpha particles are detected using a screen coated with **zinc sulfide**.

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