The radius of the aorta is «10 mm and the blood flowing through it has a speed of about 300 mm/s. a capillary has a radius of about 4ˆ10´3 mm but there are literally billions of them. the average speed of blood through the capillaries is about 5ˆ10´4 m/s. (i) calculate the effective cross sectional area of the capillaries and (ii) the approximate number of capillaries.

(I). The effective cross sectional area of the capillaries is 0.188 m².

(II). The approximate number of capillaries is

Explanation:

Given that,

Radius of aorta = 10 mm

Speed = 300 mm/s

Radius of capillary

Speed of blood

(I). We need to calculate the effective cross sectional area of the capillaries

Using continuity equation

Where. v₁ = speed of blood in capillarity

A₂ = area of cross section of aorta

v₂ =speed of blood in aorta

Put the value into the formula

(II). We need to calculate the approximate number of capillaries

Using formula of area of cross section

Put the value into the formula

Hence, (I). The effective cross sectional area of the capillaries is 0.188 m².

(II). The approximate number of capillaries is

where’s the list ? the question is incomplete

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia