# Why does a diver pull his hand and legs close to his body when jumping from diving board in the swimming pool to get more somersaults?

A diver pulls his hands and legs close to his body when jumping from a diving board in the swimming pool to get more somersaults because it helps to increase his rotational speed. In order to understand why this happens, we need to consider the principle of conservation of angular momentum.

Angular momentum is a physical property that describes the tendency of a rotating object to continue rotating in the absence of an external torque. When a diver jumps off a diving board and somersaults, he is essentially rotating around a fixed point in space.

To increase his rotational speed, he needs to reduce his moment of inertia.

The moment of inertia is a measure of how difficult it is to rotate an object. It depends on the mass of the object and how that mass is distributed relative to the axis of rotation. The closer the mass is to the axis of rotation, the lower the moment of inertia.

When a diver pulls his hands and legs close to his body, he is reducing his moment of inertia. This is because the mass of his body is now concentrated closer to the axis of rotation (i.e., the midpoint of his body).

As a result, his rotational speed increases, allowing him to complete more somersaults before landing in the water.

In addition to reducing his moment of inertia, pulling his limbs closer to his body also helps the diver maintain control over his rotation. By keeping his limbs tucked in, he reduces the amount of air resistance acting on his body, making it easier to maintain a streamlined position and control his spin.

Pulling his hands and legs close to his body is a simple yet effective way for a diver to increase his rotational speed and complete more somersaults when jumping from a diving board in the swimming pool.

It is a technique that is used by divers at all levels of skill and experience, from beginners to Olympic athletes.

## Why a diver bends his body during jump and stretches when he is about to touch water?

As a language model AI, I do not have personal experiences as human. However, I can provide a scientific explanation for why a diver bends his body during a jump and stretches when he is about to touch the water.

The answer lies in the principles of physics and the biomechanics of the human body.

When a diver jumps off a diving board, platform, or a springboard, their body is influenced by the force of gravity, the speed of their fall, and the resistance of the air. In order to execute a successful dive, the diver must control their body position and movement in order to maximize their potential for a smooth entry into the water.

Bending the body during the jump helps the diver to control their shape and trajectory as they fall through the air. By tucking the knees and pulling the body into a tight ball, the diver reduces air resistance and increases their angular momentum.

This allows them to spin faster and more efficiently, which can improve the aesthetics and technical quality of the dive.

When the diver reaches the apex of their jump and begins to descend towards the water, they must transition their body from a tucked shape to a fully extended position. This is accomplished by using their muscles and joints to straighten their legs and arms, which increases their surface area and slows their fall.

At the moment of impact with the water, the diver’s body undergoes intense forces that require a different set of movements and muscle activation. By stretching their arms and legs as they enter the water, the diver can distribute the force of impact over a larger area of their body, reducing stress on any one joint or bone.

This can prevent injury and improve the diver’s overall performance.

The reasons why a diver bends his body during a jump and stretches when he is about to touch the water are related to the physics and biomechanics of diving. By controlling their body position and movement, divers can execute technically sound and aesthetically pleasing dives that satisfy the requirements of the sport.