Explain blood flow and heart attack with the help of Bernoulli's principle.

(N/A) Bernoulli's principle states that for an incompressible, non-viscous, and steady flow, the sum of pressure energy, kinetic energy, and potential energy per unit volume remains constant.
In the human circulatory system, arteries can become constricted due to the accumulation of plaque (atherosclerosis) on their inner walls.
According to the equation of continuity $(A_1v_1 = A_2v_2)$, when the cross-sectional area $(A)$ of the artery decreases, the velocity $(v)$ of the blood flow must increase.
Applying Bernoulli's principle $(P + \frac{1}{2}\rho v^2 + \rho gh = \text{constant})$, as the velocity of blood increases in the constricted region, the internal fluid pressure $(P)$ decreases.
If the internal pressure drops significantly, the external pressure from the surrounding tissues may cause the artery to collapse.
The heart then exerts additional pressure to force blood through the constriction. As the blood rushes through the narrowed opening, the pressure drops again due to the high velocity.
This cycle of constriction and pressure drop can lead to the complete blockage of the artery, resulting in a heart attack.