a high jumpers succesfully crossed the bars. is it possible that his centre of mass crossed the bar from below it?

In the context of high jumping, it's indeed possible for a jumper's center of mass to cross the bar below it, and this can be explained through the principles of physics and biomechanics. Let's break this down step by step.

Understanding Center of Mass

The center of mass of an object is the point where its mass is evenly distributed in all directions. For a high jumper, this point is crucial because it determines how the jumper's body interacts with the bar during the jump.

Jumping Technique

High jumpers use specific techniques, such as the Fosbury Flop, which involves arching their back and leading with their head and shoulders over the bar. This technique allows them to clear the bar while keeping their center of mass below it.

Physics of the Jump

When a high jumper takes off, they generate upward momentum. As they ascend, their body rotates and bends in a way that allows their center of mass to follow a parabolic trajectory. This means that while their body may be above the bar, their center of mass can still be below it at the peak of the jump.

Analyzing the Trajectory

To visualize this, think of a basketball being thrown. The ball follows a curved path, and at its highest point, the center of the ball is not necessarily the highest point in the air. Similarly, in high jumping, the jumper's body can be positioned in such a way that the center of mass dips below the bar while the rest of the body clears it.

Practical Example

• Imagine a high jumper who arches their back significantly. As they clear the bar, their head and feet may be above the bar, but their hips and center of mass can be lower.
• This is similar to a gymnast performing a back handspring, where their body bends and rotates, allowing them to pass through a space that their center of mass does not exceed.

Conclusion on Center of Mass in High Jumping

In summary, it is entirely feasible for a high jumper's center of mass to cross the bar below it. This is achieved through a combination of technique, body positioning, and the physics of motion. The ability to manipulate body position during the jump is what allows athletes to excel in this challenging sport.