If the earth stops rotating, the apparent value of g on its surface will

Options

A. increse everywhere
B. decrease everywhere
C. remain the same everywhere
D. increase at some places and remain the same at some other places.

Answer

To solve the question regarding the effect on the apparent value of g if the Earth stops rotating, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Apparent Weight**:
The apparent weight of an object is the normal force acting on it, which is influenced by gravitational force and any additional forces acting on it, such as centrifugal force due to rotation.

**Hint**: Remember that apparent weight is the weight felt by an object, which can change due to other forces acting on it.

2. **Centrifugal Force Due to Earth's Rotation**:
When the Earth rotates, there is a centrifugal force acting outward on objects at the surface. This force reduces the effective gravitational force (g) that we feel. The formula for the centrifugal force (F_c) is given by:
\[ F_c = m \cdot \omega^2 \cdot r \]
where \( m \) is the mass of the object, \( \omega \) is the angular velocity of the Earth, and \( r \) is the radius of the Earth at the equator.

**Hint**: Consider how the rotation of the Earth affects the forces acting on an object at different latitudes.

3. **Effect of Stopping Rotation**:
If the Earth were to stop rotating, the centrifugal force would disappear. This means that the only force acting on an object would be the gravitational force. Therefore, the apparent weight would increase because the upward component of the centrifugal force is no longer present.

**Hint**: Think about how the forces balance when the centrifugal force is removed.

4. **Variation with Latitude**:
The effect of stopping the rotation will not be uniform across the globe. At the equator, the centrifugal force is at its maximum, and thus the increase in apparent weight will be significant. However, at the poles, there is no centrifugal force acting because the poles do not experience circular motion in the same way as points at the equator.

**Hint**: Analyze how the change in centrifugal force affects different locations on Earth.

5. **Conclusion**:
- At the equator and other latitudes, the apparent value of g will increase because the centrifugal force is removed.
- At the poles, the apparent value of g will remain unchanged since there was no centrifugal force acting there to begin with.

Therefore, the final conclusion is that if the Earth stops rotating, the apparent value of g on its surface will increase at most places (especially at the equator) and remain the same at the poles.

### Final Answer:
If the Earth stops rotating, the apparent value of g on its surface will increase at most places and remain the same at the poles.