Question 34:
The scattering of α-particles by a thin gold foil provides evidence for the nuclear model of the atom. Two α-particles of the same energy are incident on a nucleus of gold. Which diagram shows the correct paths followed by the α-particles as they pass close to the nucleus?
Options:
A
B
C
D
Diagram Descriptions:
General Elements: Each diagram shows a small dark circle labeled "gold nucleus" (or representing it) and two curved lines with arrows labeled "path of α-particle" (or representing them), showing particles approaching from the left and being deflected.
Diagram A: Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. The upper path curves upwards and away from the nucleus. The lower path curves downwards and away from the nucleus.
Diagram B: Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. Both paths curve downwards away from the nucleus.
Diagram C: Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. The upper path curves upwards and away from the nucleus. The lower path continues in a straight line past the nucleus without deflection.
Diagram D: Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. The upper path curves upwards and away from the nucleus. The lower path curves downwards and towards the bottom right, appearing to be deflected slightly towards the nucleus initially before turning away.
Other Relevant Text:
Label in Diagram A: "path of α-particle", "gold nucleus".---**Question 34:**
The scattering of α-particles by a thin gold foil provides evidence for the nuclear model of the atom.
Two α-particles of the same energy are incident on a nucleus of gold.
Which diagram shows the correct paths followed by the α-particles as they pass close to the nucleus?
**Options:**
* **A**
* **B**
* **C**
* **D**
**Diagram Descriptions:**
* **General Elements:** Each diagram shows a small dark circle labeled "gold nucleus" (or representing it) and two curved lines with arrows labeled "path of α-particle" (or representing them), showing particles approaching from the left and being deflected.
* **Diagram A:** Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. The upper path curves upwards and away from the nucleus. The lower path curves downwards and away from the nucleus.
* **Diagram B:** Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. Both paths curve downwards away from the nucleus.
* **Diagram C:** Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. The upper path curves upwards and away from the nucleus. The lower path continues in a straight line past the nucleus without deflection.
* **Diagram D:** Shows two parallel incoming paths of alpha particles approaching the gold nucleus from the left, one slightly above and one slightly below the horizontal line passing through the nucleus. The upper path curves upwards and away from the nucleus. The lower path curves downwards and towards the bottom right, appearing to be deflected slightly towards the nucleus initially before turning away.
**Other Relevant Text:**
* Label in Diagram A: "path of α-particle", "gold nucleus".
* Page number: 16
* Numbering: 34, 35, 36 (partially visible)
**Question 35 (Partially Visible):**
35 The half-life of carbon-14 is 5700 years.
视频信息
答案文本
视频字幕
In this alpha particle scattering experiment, we need to understand how positively charged alpha particles interact with a positively charged gold nucleus. Since like charges repel each other, the alpha particles will be deflected away from the nucleus. The particle passing above the nucleus curves upward, while the particle passing below curves downward.
Let's analyze why diagram A is correct. The upper alpha particle approaches above the nucleus and is deflected upward, away from the nucleus. The lower particle approaches below and is deflected downward, also away from the nucleus. This symmetric deflection pattern is exactly what we expect from the repulsive electrostatic force between positive charges. The other diagrams show incorrect behaviors that violate the fundamental principle of like charges repelling.