Is It Possible to Walk on Water? Unveiling the Science and Mythology

Understanding the complex interactions between forces such as buoyancy, surface tension, and pressure that determine the feasibility of walking on water.

Physics of Walking on Water

Exploring the physics behind the idea of walking on water reveals the complex interactions between forces such as buoyancy, surface tension, and pressure.

Understanding these principles allows for a deeper insight into the challenges a human would face trying to walk on water.

Understanding Buoyancy and Pressure

Buoyancy is an upward force exerted by a fluid, countering the weight of an object placed in it.

For a human to walk on water, they would require this buoyant force to be equal to or greater than their body weight.

Pressure, on the other hand, is the force applied perpendicular to the surface of an object.

The pressure exerted by a human’s feet onto the water’s surface must be supported by equal water pressure to avoid sinking.

The Role of Surface Tension

Surface tension is created by the cohesive forces between liquid molecules at the liquid-gas interface.

This tension acts like an invisible elastic membrane on the water’s surface.

Small creatures like water striders exploit this force to move across water; for humans, however, the surface tension of water is insufficient to counteract their weight without external aid.

Non-Newtonian Fluids and Water Walking

Water typically behaves as a Newtonian fluid, where its viscosity remains constant regardless of the forces acting upon it.

However, by changing the water’s properties with additives to create a non-Newtonian fluid, it’s possible to walk on it for brief periods.

For instance, adding a mixture of cornstarch to water creates a fluid that behaves solidly under sudden force, making water walking feasible in limited conditions.

Biological and Technological Approaches

A figure glides across the water's surface, a mix of biology and technology at work.</p><p>The scene is a blend of natural and man-made elements, showcasing the possibility of walking on water

While humans naturally cannot walk on water, the study of certain species and technological innovation has led us to understand and mimic the act in various ways.

Species Adapted for Surface Walking

Some species have evolved remarkable adaptations that enable them to walk or skim across the water’s surface.

The Basilisk lizard, often referred to as the Jesus Christ lizard, uses a rapid slapping motion of the feet with subsequent strokes that produce air pockets for buoyancy, allowing it to move across water without sinking.

Similarly, water striders have water-repellent legs that distribute their weight and exploit surface tension to remain afloat, effectively ‘walking’ on water.

These insects demonstrate the intricate balance of forces required to achieve this feat.

Innovations in Water-Walking Devices

Inspired by the capabilities of these species, inventors have created more than 50 water-walking devices over the last 40 years, employing concepts like pontoon-like shoes that increase the surface area of the wearer’s feet, thus providing enough lift to remain on the surface.

Experiments with non-newtonian fluids demonstrate similar principles: a mixture commonly known as oobleck, made of water and cornstarch, can behave like a solid when subjected to force, allowing objects, or even a person if moving quickly enough, to walk on its surface momentarily before it returns to a liquid state.

These devices and experiments bring a deeper understanding of the principles that allow certain species to move atop water and how they might be replicated technologically.