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What are the symbols of physical quantities in physics? It's better to have a simple explanation and formula!
The upper case P is power and the lower case P is pressure
P=W/t,
Where: P -- power, in w (watt);
W -- work, in J (joule);
T -- time, in seconds
p=F/S
Where: P -- pressure, in PA (Pascal);
F -- force, n (Newton)
S -- area, M & sup2; (square meter)
Note: electric power is also p
Electric power P = UI = u & sup2; r = I & sup2; R
Where: P -- electric power, unit: w (watt);
U -- voltage, in V (volt);
I -- current, a (ampere);
R -- resistance, in ohm
Symbol of physical quantity
All case and italics
5: Velocity s: distance t: time gravity g (n) g = Mg (M: mass; G: 9.8n/kg or 10N / kg) density: ρ (kg / m3) ρ = m / V (M: mass; V: Volume) resultant force: F (n) same direction: F (n) = F1 + F2; opposite direction: F (n) = F1-F2, opposite direction, F1 > F2 floating
Seven basic physical quantities and their special symbols
The seven basic units of the international system of units (SI)
1. Length: M
2. Mass: kg or kg (kg)
3. Time: seconds (s)
4. Current: Ampere (a)
5. Thermodynamic temperature: Kelvin (k)
6. Amount of substance: mole, referred to as mole
7. Luminous intensity: candela (CD)
What kind of physical quantity does electric work represent?
The work done by the electric field force when the current passes through a certain circuit in a period of time is called electric work. The calculation formula is w = Pt, W is electric work, and the unit is Joule
The volume of the nucleus in the atom. The electrons move at a high speed outside the nucleus
Center, minimal
The meaning of transformer symbol in electrical system diagram
For example, the graphic symbol of traction transformer. There are two triangles, one is y. but each corner of one of the triangles has an edge and an exit,
Each corner of the triangle has an edge and an outlet, which means that the coil can adjust the number of turns, similar to the extended triangle connection
What is the reason for the heating of objects? Is it the intense motion of molecules, electrons and atoms?
Boss, how do the outside world work on the object?
There are many reasons: 1. As you said, the intense motion of molecules, electrons and atoms will raise the temperature
The outside world does work on the object (push it, friction generates heat)
Distribution box system diagram symbols, letters, how to see
I have several drawings of electric power for building construction, such as system diagram of various distribution boxes and low-voltage distribution system diagram, but I can't understand who can teach the alphabet
Download GB 4728.1 ~ 10 graphic symbols for electrical diagrams
These standards contain detailed descriptions of symbols
Molecular motion + molecular vibration = heat. Isn't atomic motion + atomic vibration equal to heat?
The heat of monatomic matter is atomic motion + atomic vibration, such as iron, aluminum and other metal atoms
Polyatomic molecules are called molecules. At this time, the heat is molecular motion + molecular vibration, such as hydrogen, water and other molecules
The reason why a polyatomic molecule is not atomic motion + atomic vibration is that there is a strong interaction between atoms to form a new whole. We call this whole molecule. At this time, the heat is only reflected in the whole (i.e. molecule), not in the atoms (because the strong interaction between atoms has nothing to do with heat)
SI unit of density
In physics, the mass per unit volume of a substance is called its density
The ratio of the mass of a substance to its volume, that is, the mass of a substance per unit volume, is called the density of the substance. The symbol ρ is in kg / m ^ 3
The mathematical expression is ρ = m / v. in the international system of units, the main unit of mass is kilogram and the main unit of volume is cubic meter. Therefore, the mass of one cubic meter of material is taken as the density of material. For non-uniform material, it is called "average density"
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