What is the accurate cross-sectional area of 6-inch and 6.5-inch silicon wafers?

What is the accurate cross-sectional area of 6-inch and 6.5-inch silicon wafers?

6-inch 150 / 125 silicon wafer, 14858mm & sup2;
6.5 "165 / 125 silicon wafer, area 15483mm & sup2;
Draw 100% accuracy of automatic calculation with CAD

Is the cross-sectional area of the conductor the area of a copper wire or the area of a copper wire? For example, is the number of copper wires covered by 1 * 0.5 square and 1 * 1 mm square wires specified

It must refer to the cross-sectional area of a strand of copper wire. Of course, it's all. For example, there are 100 small copper wires in a wire with a diameter of 3cm. The total cross-sectional area is 7 square cm. Can you say it's 0.07 square cm

Conductor with cross-sectional area s,
There is a copper wire with cross-sectional area s, and the current flowing through it is I. suppose that there are n free electrons per unit area of the wire, and the electric quantity of the electrons is Q. at this time, the directional moving speed of the electrons is u. in t time, the number of free electrons passing through the cross-sectional area of a single wire can be expressed as

Current intensity: (1) definition: the ratio of the amount of electricity passing through the cross section of a conductor to the time taken to pass through the amount of electricity is called current intensity. (2) formula: I = q / T (3) unit: Ampere (a) is the basic unit in the international system of units. (4) direction: the same as the moving direction of positive charge, the same as the moving direction of negative charge

The difference between sliding rheostat and potentiometer
Such as the title
There is a kind of resistance element: blue, the same size as the thumb shell, is it called sliding rheostat or potentiometer?

Difference: sliding rheostat is usually made by winding resistance wire. It can be directly used as load or connected in series in load circuit to limit current. Potentiometer is usually film (carbon