I asked ChatGPT what the physics of surfing is and got this answer:

Surfing is a surface water sport in which the wave rider, referred to as a surfer, rides on the forward or deep face of a moving wave, which is usually carrying the surfer towards the shore. The physics of surfing involves the principles of fluid dynamics, which govern the behavior of fluids, such as water, in motion.

To understand the physics of surfing, it is first important to understand the properties of waves. A wave is a disturbance that travels through a medium, such as water or air, and carries energy from one place to another. In the case of surfing, the waves are typically generated by the wind, which blows across the surface of the water and creates ripples or waves.

The size and shape of a wave is determined by a number of factors, including the strength and direction of the wind, the distance over which the wind blows, and the topography of the seabed. The height of a wave is determined by the energy of the wind, while its length is determined by the distance over which the wind blows. The speed of a wave is determined by the depth of the water and the properties of the medium through which it is traveling.

When a surfer paddles out into the ocean and catches a wave, they are essentially riding on a moving mass of water. The surfer uses their body and surfboard to harness the energy of the wave and ride it towards the shore. The surfer’s body and surfboard act as a hydrofoil, which is a device that uses the principles of fluid dynamics to generate lift and propulsion.

The surfboard is designed to cut through the water and create lift, which propels the surfer forward. The surfer’s body position and movements also play a crucial role in generating lift and maintaining control on the wave. The surfer can use their body weight, their stance, and their arm and leg movements to steer the surfboard and control their speed and direction on the wave.

In summary, the physics of surfing involves the principles of fluid dynamics, which govern the behavior of water in motion. The surfer uses their body and surfboard to harness the energy of the wave and ride it towards the shore, using the principles of hydrofoil design to generate lift and propulsion.