An octopus propels itself through the water by injecting water through a funnel and its body. How does this demonstrate newtons third law?
Newton's third law states that for every action, there is an equal and opposite reaction. When the octopus injects water through its funnel, it exerts a force on the water in the opposite direction. As a result, the water exerts an equal and opposite force on the octopus, propelling it forward.
In this case, when the octopus injects water through its funnel and body, it creates a jet propulsion system. By contracting its mantle (a muscular structure), the octopus expels water with force through its funnel. As a consequence, according to Newton's third law, the expelled water exerts an equal and opposite force on the octopus's body. This reaction force pushes the octopus in the opposite direction, propelling it through the water.
The action is the expulsion of water using muscular contractions, and the reaction is the resulting forward movement of the octopus due to the force exerted by the expelled water. Therefore, the octopus's method of propulsion clearly demonstrates Newton's third law.