The wheels of moving vehicles are made hollow in the middle and thick at the periphery, because

Options

A. it gives minimum moment of ineretia to the tyre
B. its shape is a strong one
C. this increases the speed
D. it increases moment of inertia of tyre

Answer

To answer the question regarding why the wheels of moving vehicles are made hollow in the middle and thick at the periphery, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Moment of Inertia**:
- The moment of inertia (I) of an object is a measure of how difficult it is to change its rotational motion about an axis. It depends on the mass distribution relative to that axis.
- The formula for moment of inertia for a point mass is given by \( I = m \cdot r^2 \), where \( m \) is the mass and \( r \) is the distance from the axis of rotation.

2. **Design of the Wheel**:
- The wheels of vehicles are designed to be hollow in the middle and thicker at the periphery. This design allows for a distribution of mass that is concentrated further away from the axis of rotation.
- By making the wheel hollow, we reduce the mass located near the center, while the mass at the periphery (outer edge) is maximized.

3. **Effect on Moment of Inertia**:
- When the mass is concentrated at a larger radius (the periphery), the moment of inertia increases because the distance \( r \) in the formula \( I = m \cdot r^2 \) is larger.
- An increased moment of inertia implies that the wheel has greater resistance to changes in its rotational state.

4. **Implications for Vehicle Motion**:
- A higher moment of inertia means that once the wheel is in motion, it will tend to stay in motion due to its rotational inertia. This is beneficial for vehicles as it helps maintain speed and stability.
- It also contributes to better traction and control, especially when accelerating or going over uneven surfaces.

5. **Conclusion**:
- Therefore, the design of the wheels being hollow in the middle and thick at the periphery is primarily to **increase the moment of inertia**, which enhances the vehicle's performance by improving stability and maintaining speed.