Final answer:
The concept of selecting the appropriate syringe size for a CAD flush relates to physics principles, specifically fluid dynamics. By calculating the areas of a syringe barrel and needle, one can determine the flow rate and liquid velocity using the plunger's movement rate.
Step-by-step explanation:
When discussing syringe sizes for a CAD (Coronary Artery Disease) flush, it's crucial to use a syringe that minimizes resistance and ensures safe and effective delivery of the flushing solution. To calculate the flow rate and velocity of a liquid in a syringe, one needs to understand the principles of fluid dynamics, which is a topic within physics.
Using the provided syringe dimensions, we can calculate the area of both the barrel (A₁) and the needle (A₂) using the formula for the area of a circle, A = πr², where r is the radius. The barrel has a diameter of 1.2 cm, so its radius is 0.6 cm, and the area A₁ is π*(0.6 cm)². The needle has a diameter of 2.4 mm, so its radius is 1.2 mm, or 0.12 cm, and the area A₂ is π*(0.12 cm)².
Next, the flow rate in the barrel can be calculated given that the plunger moves at a rate of 4.0 mm/s. The velocity of the liquid in the needle will be higher than in the barrel, as the cross-sectional area of the needle is smaller, resulting in a faster flow to maintain the continuity of the flow rate (continuity equation).