A skateboarder hits a small rock which stops their skateboard, but their body continues to move forward. Explain why this is the case.

Answer 1

This situation can be explained by the principle of inertia. Inertia is the tendency of an object to resist changes in its motion, either to remain at rest or continue moving in a straight line at a constant velocity.

When the skateboarder hits a small rock, the contact between the rock and the skateboard causes a sudden change in the skateboard's motion. However, the skateboarder's body, which is separate from the skateboard, continues to move forward due to its inertia.

This happens because the skateboarder's body is not directly connected to the skateboard, besides the feet which are in contact with the board. So, when the skateboard stops due to the rock, the feet experience a sudden force that causes them to stop instantly. However, the rest of the body, with no immediate external force acting on it, tends to maintain its forward motion due to inertia.

Consequently, the skateboarder's body keeps moving forward after the skateboard is stopped, potentially leading to a fall or loss of balance if they cannot adjust to the sudden change in motion caused by the rock.