Electric energy meter is used to measure electric power, current, power and voltage which one?

Electric energy meter is used to measure electric power, current, power and voltage which one?

The electric energy meter is used to measure the work done by electrical appliances in unit time, that is, electric work;
The ammeter is used to measure the current, the voltmeter is used to measure the voltage, and the electric power is the physical quantity indicating the speed of the current work, which cannot be measured by the electric energy meter

Electric power, more formula how to calculate the number of turns of the meter
More formula how to calculate, current, electricity time and power!

I=W/P
T=W/P
W=UIT=I^2RT=U^2/RT

If the median line length of the trapezoid is 3 and the height is 2, the area of the trapezoid will be smaller

3*2=6
The median line length is equal to half of the sum of the upper and lower bottoms
The area of the trapezoid is equal to the sum of the upper and lower base multiplied by the height divided by 2, so you can directly multiply the height by the length of the median line

The correct use of the scale: (1) when reading, the line of sight should be consistent with (), and when measuring accurately, you should read ()

Measurement of length and use of scale: ① before use, pay attention to observe its zero scale, range and minimum scale value; ② when measuring with scale, the scale should be along the measured length without using the worn zero scale; ③ when reading, the line of sight should be perpendicular to the scale surface, and when measuring accurately, the line of sight should be perpendicular to the scale surface, (1) the difference between the measured value and the real value is called error; (2) the error can only be reduced as far as possible, but can not be eliminated; (3) the error can be reduced by selecting precision measuring tools, improving the measuring method and improving the measuring level, It is the most effective way to reduce the error to calculate the average value by multiple measurements. The average value should be calculated to one more digit than the measured value and then rounded, that is, the average value should retain the same digit as the measured value (only one estimated digit)

If the ratio of the top and bottom of the trapezoid is 1:3, then the area ratio of the two trapezoids divided by the median line is?

If the upper bottom of trapezoid is 1, the lower bottom is 3, the median line is 2, and the height is the same
So the area ratio of the two trapezoids is (1 + 2): (2 + 3) = 3:5

The reading should start from the high position, and the addition and subtraction should start from ()

The reading should start from the high position, and the addition and subtraction should start from the low position
Or: the reading should start from the high position, and the calculation of addition and subtraction should start from (individual position)

The area of the trapezoid is divided into two parts by a diagonal. What is the area ratio of the two parts of the trapezoid divided by its median line?

3:5

When measuring the volume of gas with the method of discharging liquid, why should the reading move the tube on one side of the connector up and down to make the left and right tubes level?

When reading, the liquid level at both ends should be adjusted to keep level, so as to make the gas equal to the atmospheric pressure of the outside world, so as to reduce the error of the experiment. If the water on the gas side is lower, the volume of the measured gas is smaller; if the water on the gas side is higher, the volume of the measured gas is larger

If the ratio of the top and bottom of the trapezoid is 5:15, what is the area ratio of the median line dividing the trapezoid into two trapezoids

5: 15 is 1:3
Let the upper bottom of trapezoid be x and the lower bottom be 3x
The length of the trapezoidal median line is 1 / 2 of the sum of the upper and lower bottoms
So the median line can be expressed as 2x
Because the heights of the upper and lower trapezoids are equal, set H
So the area ratio of trapezoid is (1 x + 2 x) H / 2: (2 x + 3 x) H / 2 = 3:5

Do you need to estimate the next digit when the pallet balance measures the mass of the material

When the pallet balance is used to measure the mass of material, the reading of traveling code needs to be estimated to the next position of the minimum scale