Does the 220 V voltage of the utility power mean that the effective value is 220 V or the peak value is 220 V?

Does the 220 V voltage of the utility power mean that the effective value is 220 V or the peak value is 220 V?


The 220 V voltage of the utility refers to that the RMS is 220 V, and its single peak value is twice the root of the RMS. That is 220 * 1.414, which is about 310 v. the peak to peak value is the difference between the positive peak value and the negative peak value = 310 V - (- 310 V) = 620 v



The relationship between current and voltage in series and parallel circuits?


In series: I = I1 = I2 =. = in
U=U1+U2+.+Un
Parallel: I = I1 + I2 +. + in
U=U1=U2=.=Un



How to calculate the current and voltage in series and parallel circuits


In parallel connection, the total voltage is equal, the total current is equal to the current of each parallel branch, and the total current is equal to the current of each parallel branch
Series connection means that the total current is equal and the total voltage is equal to the sum of the voltages on each component
To put it simply, it is shunt in parallel and partial pressure in series



Simplified fraction: (2A2 + 3A + 2) / A + 1 - (a2-a-5) / A + 2 - (3a2-4a-5) / A-2 + (2a2-8a + 5) / A-3


-12- 3/a



Put the nine numbers - 2, - 1,0,1,2,3,4,5,6 into the nine palace lattice respectively, so that each row, each column and the diagonal


1 6 -1
0 2 4
5 -2 3



Using substitution elimination method to solve equations 3 (Y-2) = x-17,2 (x-1) = 5y-8


3(y-2)=x-17,
3y-6=x-17
So x = 3Y + 11
Substituting 2 (x-1) = 5y-8
2(3y+11-1)=5y-8
6y+20=5y-8
y=-28
x=3y+11=-73



How to write question 2.3.4 on page 6 of supplementary exercises in Volume I of sixth grade mathematics of Jiangsu Education Press


2. 120x-85x=52.5
3. 324x-319x=120
4. 1.8x-1.2x=54



If the value of algebraic formula 2 times the square of X + 3 times x + 7 is 12, find the value of algebraic formula 4 times the square of X + 6 times X-10


2x^2+3x+7=12
2x^2+3x=5
4x^2+6x-10
=2(2x^2+3x)-10
=2*5-10
=0



How to calculate 1.3 divided by 0.7 + 0.8 divided by 0.7


=(1.3+0.8)x10÷7
=3



Given that the perimeter of triangle is 8, how to find the area
If the point E (x, 0) moves on the line AB and the point F moves on the broken line ACB, when the line EF bisects the perimeter of the triangle ABC, let the area of the triangle AEF be y, and find the relationship between Y and X. (where AB is on the X axis, the perimeter of the triangle ABC is 16, the triangle AFE is 8, a (- 3,0), C (4,0), B (3,0))
The number of C is (0,4) wrong. It should be AE + AF = 8. I have the wrong number


Is the perimeter of the triangle AFE 8? If EF bisects the perimeter of the triangle ABC, shouldn't AE + AF = 8?