Question

1. what is the name of this symbol?

Explanation:

The symbol shown (a horizontal line with a rectangle on it, often representing a resistor in electrical circuit diagrams, or in other contexts like a "bar" or "overline" in typography/mathematics, but more likely a resistor symbol in electronics. However, if considering the visual as a "resistor" symbol in electrical engineering (a subfield of Engineering under Natural Science), or if it's a mathematical overline (for denoting mean, etc., in Statistics/Mathematics). But the common interpretation for this visual (a short horizontal line with a rectangle on it, extended slightly) is a resistor symbol in electrical engineering (Engineering subfield of Natural Science) or a overline (in Mathematics for notation like $\overline{X}$ for mean). If focusing on the most common technical symbol, it's a resistor (used in circuit diagrams, part of Engineering).

Answer:

The symbol is commonly known as a "resistor" (in electrical engineering, for circuit diagrams) or an "overline" (in mathematics/typography for notation like denoting a mean or a line over a character). If referring to electrical engineering, it's a resistor symbol.