If r = 1K ohm, C = 0.5 micromethod, we can find ur, UC, | ur / UC And the phase difference between capacitance and circuit is expressed by vector diagram

If r = 1K ohm, C = 0.5 micromethod, we can find ur, UC, | ur / UC And the phase difference between capacitance and circuit is expressed by vector diagram

The impedance of the capacitor is Z = 1 / (JWC), the frequency is w = 1 / RC, and j is an imaginary unit
Z=-jR
Ur=RI
Uc=Z*I=-jRI
Ur+Uc=U
Ur=(1+j)/2*U
Uc=(1-j)/2*U
|Ur | = | UC | = u / sqrt (2), the phase difference is pi / 2

RC series circuit, known r = 1 / WC = 10 Ω, connected to u = (10 + 20 root 2sinwt) V non sinusoidal voltage, calculate the capacitor voltage UC
The answer is 10 + 20sin (wt-45 °)

Using superposition theorem, the voltage source is decomposed into 10 V DC power supply and 20 root 2 sinwt AC power supply
When the 10 V DC power supply acts alone, the circuit is equivalent to an open circuit, and the voltage at both ends of the capacitor is equal to the supply voltage, uc1 = 10 v
When the AC power supply acts alone, u = 20

I want to ask for a set of math problems for the first grade of kindergarten big class examination!
In September of this year, I took the first grade exam and asked for some helpful questions,

First, from 1 to 10 2, look at the picture and write the number () () 3, look at the picture and fill in the number () + () = 56 - () = 40 + () = () - () = 0 3 () 1 () 22 4, count one number and fill in the blank () ()

Given the equation 3x + 2y-4 + 3 α x-2by = 0 about X and y, if there is no X term, find the value of α

(3+3a)X+(2-2B)Y-4=0
Because there is no X term, the coefficient of X is 0
So 3 + 3A = 0
A=-1/3

As of 2004, China's desertification land area is about 2.64 million square kilometers. What percentage of the land area is desertification land? (please know the land area of China first.)
The above is the question. First, help me find out the land area of our country, and then write the formula in the answer. If it's right, add points. Be sure to write the formula! There's another answer! Whoever can answer, the sooner the better,

China's land area is about 9.6 million square kilometers
So the formula is: 2640000 / 9600000 * 100% = 27.5%

It is known that the line y = KX + B is parallel to the line y = minus two fifths X and intersects with the hyperbolic y = minus x molecule 5 at point (m, 1),
Find the analytical formula of this line (with process)

It is known that the line y = KX + B is parallel to y = - 2 / 5x
This line is y = 2x / 5 + B
∵ intersects hyperbola y = - 5 / X at point (m, 1)
∴1＝﹣5／m ∴m=﹣5
The line y = 2x / 5 + B passes through the point (- 5,1)
∴2×﹙﹣5﹚／5＋b=1 ∴b=3
This line is y = 2x / 5 + 3

Before the brackets is a plus sign, remove the brackets {}; after the plus sign, add brackets, inside the brackets {}; inside the brackets is a minus sign, remove the brackets {}
The minus sign is followed by brackets in which {}_

Invariant sign; invariant sign; variable sign; variable sign
It is how to remove brackets, such as 5 - (3 + 2-8) = 5-3-2 + 8;
7+（4-3+8）=7+4-3+8
If you look at it directly, you will get rid of the brackets. If you look back, you will get parentheses

Quadratic equation of one variable and quadratic function problem
1. When m takes what value, the parabola y = x ^ 2 and the straight line y = x + M
(1) There is a common point (2) there is no common point

If there is a common point, just see if x ^ 2-x-m = 0 has a root
△=1+4m
If there is a common point, then △ > = 0, that is, M > = - 1 / 4
If there is no common point, then △

Key points: division sign, plus sign, multiply sign, minus sign and fraction are all replaced by Chinese characters, with units, answers and answers
1. There are 45 students in class 5 (1), Among them, there are 21 boys. What percentage of the total number of boys and girls in the class? What percentage of the total number of boys and girls? What percentage of the total number of girls? 2. A batch of 600 tons of goods has been transported away by 250 tons. (1) what percentage of the goods has been transported away? (2) what percentage of the remaining goods? 3. Xiao Hua and Xiao Ming read the same book It took Xiaohua 30 days to finish the book, and Xiaoming 25 days to finish it. They read it for 5 days each. What percentage of the book did they read? In April and November (30 days), Xiaohua's mother worked for 4 days and had a rest for 1 day, Xiaohong's father worked for 2 days and had a rest for 1 day, Xiaohong has a rest on Saturday and Sunday. Xiaohong's family (three people) have a rest on two days at the same time. The three people go to see their grandfather together. They are going to visit the museum at the next time when they have a rest at the same time. What's the number of visiting the museum? 5. The numerator and denominator of the score of 97 out of 181 minus the same number, and the new score is about 2 out of 5, So what's the subtraction number? This is the knowledge of Volume 2 of grade 5! Division sign, plus sign, multiplication sign, minus sign and fraction are all replaced by Chinese characters, which must be solved at one time

1. The number of male students in the class: 21 △ 45 = 7 / 15, the number of female students in the class: 45-21 = 24 (people) 24 △ 45 = 8 / 15, the number of male students is female students: 21 △ 24 = 7 / 8, the number of female students is male students: 24 △ 21 = 8 / 7 = 1 and 7 / 12

The square factorization of the square of (a-b) - C

The square factorization of the square of (a-b) - C
=（a-b+c）(a-b-c)
If you don't understand this question, you can ask,