Final answer:
Rotating, high pressure oil from a plug or sprayer plate is due to fluid dynamics, with force exerted on a plunger causing high pressure that leads to increased oil speed through a narrow opening, and it's explained by Bernoulli's principle and the Continuity Equation.
Step-by-step explanation:
The most likely cause of rotating, high pressure oil coming out of a plug or sprayer plate is related to the principles of fluid dynamics, specifically Bernoulli's principle and the conservation of energy in the system. When a force is applied to a plunger, like in the example of a horizontally oriented squirt toy, it causes the pressure in the fluid (in this case, the oil) to increase. This pressure is transmitted and acts on the fluid throughout the system.
According to Bernoulli's principle, as the oil is forced through a narrow opening, it must increase in speed to conserve energy. This can result in oil emerging at high speed and pressure, often rotating due to the design of the nozzle or sprayer plate, akin to a hydraulic press mechanism that evenly distributes pressure across the oil. In technical terms, the speed and pressure with which the oil is expelled are determined by the Continuity Equation and Bernoulli's Equation, considering the force applied, cross-sectional areas of the openings, and atmospheric pressure influence.