Why does a person tend to fall when he jumps out from a moving train and tries to stop immediately?

Explanation

### Step-by-Step Solution:

1. **Understanding the Situation**: When a person jumps out of a moving train, they are initially moving at the same speed as the train. This means that both their lower body and upper body are in motion.

2. **Jumping Out of the Train**: As the person jumps out, their lower body makes contact with the ground first. At this moment, the lower body begins to decelerate and eventually comes to a stop.

3. **Inertia of the Upper Body**: According to Newton's First Law of Motion, an object in motion will remain in motion unless acted upon by an external force. The upper body of the person still has the momentum from the speed of the train.

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