Measure of inertia in translatory motion is

Options

A. mass
B. momentum
C. impulse
D. force

Answer

To solve the question "Measure of inertia in translatory motion is", we need to understand the concept of inertia and how it relates to mass in the context of translatory (linear) motion.

### Step-by-Step Solution:

1. **Understanding Inertia**:
- Inertia is the property of an object to resist changes in its state of motion. It is a measure of how much an object will resist acceleration when a force is applied.

2. **Translatory Motion**:
- Translatory motion refers to the motion of an object moving from one point to another in a straight line. In this type of motion, the object can have different velocities and accelerations.

3. **Newton's Second Law of Motion**:
- According to Newton's second law, the force (F) applied to an object is equal to the mass (m) of the object multiplied by its acceleration (a). This is expressed mathematically as:
\[ F = m \cdot a \]

4. **Effect of Mass on Force**:
- If we consider an object with mass \( m \) that is accelerated with \( a \), the required force is \( F = m \cdot a \).
- If the mass is increased to \( 2m \) while keeping the acceleration \( a \) the same, the new force required becomes:
\[ F' = 2m \cdot a \]
- This shows that a greater mass requires a greater force to achieve the same acceleration.

5. **Conclusion**:
- From the above reasoning, we can conclude that the measure of inertia in translatory motion is directly related to mass. The greater the mass of an object, the greater its inertia, meaning it will resist changes to its state of motion more than an object with less mass.

Thus, the measure of inertia in translatory motion is **mass**.