A physicist, biologist and a chemist were going to the ocean for the first time.

The physicist saw the ocean and was fascinated by the waves. He said he wanted to do some research on the fluid dynamics of the waves and walked into the ocean. Obviously, he was drowned and never returned.

The biologist said he wanted to do research on the flora and fauna inside the ocean and walked inside the ocean. He too, never returned.

The chemist waited for a long time and afterwards, wrote the observation, "The physicist and the biologist are soluble in ocean water".

Reminds me of this one:

A biologist, a physicist and a mathematician are sitting in a train. Through the window they see a horse galloping in a field.

The biologist starts: "The horse is breathing, oxygen is carried by the blood to the muscles where it reacts with glucose, resulting in the production of energy to contract the muscles. Meanwhile electric signals travel from the brain along the nerves to coordinate the contraction of the muscles. These phenomena together allow the horse to run."

The physicist adds: "The weight of the horse puts pressure on the ground, which is balanced by a reaction force. As the horse moves its legs up and down, it applies additional forces on the ground. If you do the sum of these forces, you'll find that the resulting force is directed forward and is equal to the weight of the horse multiplied by its acceleration, and so the horse can run."

The mathematician is silent for a while. Then he says: "Firstly, let us assume that the horse is a sphere..."