Which of the following statement is wrong?

Options

A. The moment of linear momentum is a vector quantity
B. The moment of the mass is called moment of inertia
C. The moment of linear momentum is called angular momentum
D. The moment of a force is called torque.

Answer

To determine which statement is wrong among the given options, we will analyze each statement one by one.

### Step 1: Analyze Statement A
**Statement A:** "The moment of linear momentum is a vector quantity."

- **Explanation:** The moment of linear momentum, also known as angular momentum (L), is defined as the cross product of the position vector (r) and the linear momentum vector (p). Mathematically, it is expressed as:
\[ L = r \times p \]
Since both r and p are vector quantities, their cross product is also a vector quantity. Therefore, this statement is **correct**.

### Step 2: Analyze Statement B
**Statement B:** "The moment of mass is called moment of inertia."

- **Explanation:** The term "moment of mass" is not a standard term in physics. The correct term is "moment of inertia," which is defined as the sum of the products of the mass of each particle and the square of its distance from the axis of rotation. It is given by:
\[ I = \sum m_i r_i^2 \]
where \( m_i \) is the mass of the particle and \( r_i \) is the distance from the axis of rotation. The statement incorrectly equates "moment of mass" with "moment of inertia." Therefore, this statement is **incorrect**.

### Step 3: Analyze Statement C
**Statement C:** "The moment of linear momentum is called angular momentum."

- **Explanation:** As previously stated, the moment of linear momentum is indeed defined as angular momentum. Thus, this statement is also **correct**.

### Step 4: Analyze Statement D
**Statement D:** "The moment of force is called torque."

- **Explanation:** The moment of force, commonly referred to as torque (τ), is defined as the product of the force (F) and the distance (r) from the pivot point, expressed as:
\[ \tau = r \times F \]
This definition is accurate, making this statement **correct**.

### Conclusion
After analyzing all the statements, we find that:
- Statement A: Correct
- Statement B: **Incorrect**
- Statement C: Correct
- Statement D: Correct

Thus, the wrong statement is **Statement B**.