The lithium battery used on the mobile phone is marked with "3.6V & nbsp; & nbsp; 900mA. H". Please estimate the energy that this battery can store______ J．

The lithium battery used on the mobile phone is marked with "3.6V & nbsp; & nbsp; 900mA. H". Please estimate the energy that this battery can store______ J．

According to the definition formula of current I = QT: q = it = 900mAh = 900 × 1 × 10-3a × 3600s = 3120c, the battery can store electric energy w = uit = UQ = 3.6V × 3120c = 11232j

How to calculate 2 out of 7 * 3 out of 11 / (2 out of 7 * 3 out of 11)

What did Joule find?

Joule's law

Lianyilian: 0, 4252, 0452, 750, 450, 322, 242, 3 / 4, 9 / 20, 8 / 25
In a row:
0、425 2、045 2、75 0、45 0、32 2、24
2 and 4 / 3, 20 / 9, 25 / 8, 40 / 17, 2 / 200 / 9, 2 / 25 / 6

1 2 3 4 5 6
Below: 4 5 1 2 3 6

We want to change the sensitive ammeter with 100 μ a range and 500 ohm internal resistance into a Ma meter with 1mA range
If you want to change a sensitive ammeter with 100 μ a range and 500 ohm internal resistance into a milliammeter with 1mA range, how to change it? How much resistance do you need to connect?

Connect a 500 / 9 ohm resistor in parallel,
1. In series, the current is constant, so it can only be connected in parallel. At this time, the shunt resistance makes the range larger
2. After parallel connection, the total current increases 10 times, and the shunt current is 9 times of the current through the ammeter, so the parallel resistance is 1 / 9 of the internal resistance

A shop sells a kind of tourist souvenir of Mount Tai. The turnover in April is 2000 yuan. In order to expand the sales volume, the shop sells this kind of souvenir at a 10% discount in May. As a result, the sales volume increases by 20 pieces and the turnover increases by 700 yuan. (1) ask the sales price of this kind of souvenir in April; (2) if the profit of this kind of souvenir is 800 yuan in April, how much profit will it make in May?

(1) Let the selling price of this kind of souvenir in April be x yuan. According to the meaning of the title, we get 2000x = 2000 + 7000.9x − 202000x = 3000x − 201000x = 2020x = 1000, and the solution is x = 50. It is proved that x = 50 is the solution of the original fractional equation, and it is in line with the practical significance. The selling price of this kind of souvenir in April is 50 yuan. (2) from (1) we know that the number of pieces sold in April is 200050 = 40, and 〈 in April The profit of each piece is 80040 = 20 yuan. The number of pieces sold in May is 40 + 20 = 60, and the price of each piece is 50 × 0.9 = 45 yuan. The profit of each piece is 5 yuan less than that in April, which is 20-5 = 15 yuan. Therefore, the profit of selling this kind of souvenir in May is 60 × 15 = 900 yuan

The output voltage of the generator is 220 V, the output power is 44 kW, and the resistance of each transmission line is 0.2 Ω. How much is the voltage and electric power obtained by the user? If the power station first uses the step-up transformer with the transformation ratio of 1:10 to increase the voltage, and then supplies it to the user through the same transmission line, and then through the step-down transformer with the ratio of 10:1, what is the voltage and electric power obtained by the user?
I=P0/U0=44000/220=200A
Δ u = IR = 200 × (2 × 0.2) v = 80 V, why do you use resistance 0.2 Ω times 2 here?

One loop~
One line is from the generator to the consumer, and the other is from the consumer to the generator;
1: 10 boost, the current will become one tenth of the original, the line voltage drop will become 8V, the user voltage will be 212v, and the current will be 200A

Life is a teacher!
Note: soliciting articles
First line: title
The second line: school class name, correspondence address, contact telephone, postal code
The third line: Zhengwen No.4
thank you

Life is a teacher, life is like a palette, which contains colorful colors, used to bring out other colorful colors, these colors are like different flavors, make me feel the colorful life, full of flavor. Bitter. "Really tired!" I sighed, put down the pen in hand, leaning on the back of the chair

If angle 1 plus angle 2 equals 90 degrees and angle 1 plus angle 3 equals 90 degrees, then the relationship between angle 2 and angle 3 is the reason

Professional teachers will serve you. If you don't understand, please discuss,
Equal
The reason is that equal substitution angle 1 + angle 2 = angle 1 + angle 3, that is, angle 2 = angle 3

-A & # 179; + A & # 178; B-1 / 4AB & # 178; factorization

-a(a-1/2b)^2