Which of the following statement is not true regarding einsteins mass energy relation?

Options

A. Mass disappears to reappear as energy.
B. Energy disappears to reappear as mass
C. Mass and energy are two different forms of the same entity.
D. Mass and energy can never be related to each other.

Answer

To solve the question regarding which statement is not true about Einstein's mass-energy relation, we can follow these steps:

### Step 1: Understand Einstein's Mass-Energy Relation
Einstein's mass-energy relation is expressed by the equation \( E = mc^2 \). This equation states that mass (m) can be converted into energy (E) and vice versa, where \( c \) is the speed of light in a vacuum.

### Step 2: Analyze the Statements
We need to evaluate the provided statements to determine which one is not true. The statements typically include:
1. Mass disappears to appear as energy.
2. Mass can be converted to energy.
3. Energy disappears to reappear as mass.
4. Mass and energy can never be related to each other.

### Step 3: Evaluate Each Statement
- **Statement 1**: Mass disappears to appear as energy.
- This is true as mass can be converted into energy.

- **Statement 2**: Mass can be converted to energy.
- This is true and is a direct implication of the mass-energy equivalence.

- **Statement 3**: Energy disappears to reappear as mass.
- This is also true, as energy can be converted back into mass.

- **Statement 4**: Mass and energy can never be related to each other.
- This statement is false. According to Einstein's theory, mass and energy are interrelated.

### Step 4: Identify the Incorrect Statement
From the evaluation, the statement that is not true is:
- **Statement 4**: Mass and energy can never be related to each other.

### Conclusion
The correct answer to the question is that the statement which is not true regarding Einstein's mass-energy relation is **Statement 4**.

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