A ball is thrown vertically upward. What is the magnitude of velocity at the highest point ?

Explanation

To solve the problem of finding the magnitude of velocity at the highest point when a ball is thrown vertically upward, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Motion**: When a ball is thrown vertically upward, it moves against the force of gravity until it reaches its highest point. At this point, the ball momentarily stops before it starts to fall back down.

2. **Identifying the Highest Point**: At the highest point of its trajectory, the ball has reached the maximum height. This is the point where the upward velocity becomes zero before the ball starts descending.

3. **Applying the Concept of Velocity**: The velocity of an object is defined as the rate of change of its position with respect to time. At the highest point, the ball is not moving upward or downward; therefore, its velocity is zero.

4. **Conclusion**: Since the velocity at the highest point is zero, we can state that the magnitude of the velocity at this point is:
\[ v = 0 \, \text{m/s} \]

### Final Answer:
The magnitude of velocity at the highest point is **0 m/s**.

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