A man getting down a running bus falls forward because

Options

A. due to inertia of rest, road is left behind and man reaches forward
B. due to inertia of motion upper part of body continues to be in motion in forward direction. While feet come to rest as soon as they touch the road
C. he leans forwards as a matter of habit
D. of the combined effect of all the three factors stated in (a), (b) and (c )

Answer

To solve the question "A man getting down a running bus falls forward because," we need to analyze the situation using the concept of inertia from Newton's first law of motion.

### Step-by-Step Solution:

1. **Understanding Inertia**: Inertia is the property of an object to resist changes in its state of motion. An object in motion will continue to stay in motion unless acted upon by an external force.

2. **Situation Analysis**: When a man is inside a running bus, both he and the bus are moving forward at the same speed. When he decides to get down from the bus, he is effectively changing his state of motion.

3. **Jumping Down**: As the man jumps down from the bus, his feet make contact with the ground (the road). At this moment, his feet come to a stop because they are now in contact with the ground.

4. **Upper Body Motion**: However, due to inertia, the upper part of his body (which was moving forward with the bus) continues to move forward at the same speed it was moving before he jumped down. There is no immediate force acting on the upper body to stop it.

5. **Resulting Motion**: Since the lower part of his body (the feet) stops when they hit the ground, but the upper part continues to move forward, this causes him to lean forward and potentially fall.

6. **Conclusion**: The reason the man falls forward is primarily due to the inertia of motion. The upper part of his body continues to move forward while the lower part comes to rest.

### Final Answer:
The man falls forward because of the inertia of motion; the upper part of his body continues to move forward while his feet come to rest upon touching the road.

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