A nucleus is bombarded with a high-speed neutron so that resulting nucleus is a radioactive one. This phenomenon is called

Options

A. Artificial radioactivity
B. Fusion
C. Fission
D. Radioactivity

Answer

To solve the question, we need to understand the process that occurs when a nucleus is bombarded with a high-speed neutron, resulting in a radioactive nucleus. Here’s the step-by-step solution:

### Step 1: Understand the Bombardment Process
When a high-speed neutron collides with a nucleus, it can cause the nucleus to become unstable. This instability can lead to the nucleus undergoing a transformation.

**Hint:** Consider what happens to a nucleus when it absorbs a neutron. Does it become more stable or unstable?

### Step 2: Identify the Resulting Reaction
The bombardment of a nucleus by a neutron can lead to two primary outcomes: fission or fusion. In this case, since the question specifies that the resulting nucleus is radioactive, we are likely dealing with fission.

**Hint:** Recall the definitions of fission and fusion. Which process involves the splitting of a nucleus?

### Step 3: Define Fission
Fission is the process where a heavy nucleus splits into two or more smaller nuclei, along with the release of energy. This process often occurs in heavy elements like uranium or plutonium when they absorb a neutron.

**Hint:** Think about the term "fission" and what it implies regarding the number of nuclei before and after the reaction.

### Step 4: Conclusion
Based on the understanding that the bombardment of a nucleus by a neutron leads to the disintegration of that nucleus into smaller parts, we conclude that this phenomenon is called fission.

**Final Answer:** The phenomenon is called **fission**.