Find the size of the voltage U, find the value of the voltage U in the circuit, thank you!

How are the specifications and dimensions of the U-shaped screwdriver marked? -Electricity. Let's talk about flashlights.

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We know that there are several important parameters of the battery, which are the operating voltage (V), milliampere-hours (mAh), and me.

November 9, 2017.

Science**: The voltage size of the Apple battery is the depth at which the electrodes are inserted into the apple.

1) The voltmeter is connected to both ends of the battery through the switch, and the circuit diagram is shown in the figure; (2) During the experiment, other conditions should be kept unchanged, and only the depth of the electrode inserted into the apple should be changed; (3) From the circuit diagram, the voltmeter range is 3V, and the minimum graduation value of the voltmeter is the voltmeter.

Homework helps with a lesson.

Selection of battery capacity—Calculation method of battery selection Library.

Selection of battery capacity - calculation method of battery selection electric power and water conservancy engineering. The basic calculation is as follows: Maximum DC bus voltage u max = 48 1....

Library. How to calculate the power of the battery [Juda lithium battery].

The instructions indicate that the operating current of the device is large, and the battery of small capacity is not. i=p u=300 12=25 amps. If it does not exceed the battery rating.

How is battery capacity (mAh) calculated?

What is the voltage ratio when the battery voltage is full after the battery capacity is depleted?

I'll answer. 7 articles.

Tao Ah Tao II from the Know Certification Team 2018-09-16

1. Calculation method of battery capacity (c): capacity c discharge battery (constant current) i discharge time (hours) t

Reverse: Discharge time t capacity c Discharge current (constant current) i

For example, if a battery is discharged with a constant current of 500mA (milliampere) for 2 hours, then the capacity of this battery is equal to 500mA * 2h 1000mAh = 1ah and if a battery is discharged with a current of 5 amps for 2 hours, then the capacity of the battery is 10ah

2. What is the voltage difference between the full and discharged batteries? In fact, this is related to the type and type of battery, different types of batteries are different, such as lithium batteries for mobile phones, rated voltage, the lowest voltage is 3V, and lead-acid batteries are rated at 2V and the lowest voltage. If it is a 12V lead-acid battery, the rated voltage is 12V, which is the lowest.

Extended information: The rechargeable battery whose capacity has been reduced can be charged by the excitation method to restore the rechargeable battery capacity to its original state, as follows:

1. Put the remaining current of the battery clean first: you can discharge it with a flashlight or a small bulb until the filament of the flashlight or small bulb is red. Note: Do not allow the voltage of the battery to drop when discharging.

After acceptance, you will be calculated"Process.

Convert the current source to a voltage source (12V and 10 in series). Total voltage 12-3 = 9V

By the principle of resistance voltage division:

u=9×70/(70+10+2)≈

First, find the branch current, and calculate it as follows.

After acceptance, you will be calculated'Process.

As potential difference or potential difference, it is a physical quantity that measures the energy difference between a unit charge in an electrostatic field due to different electric potentials. Its magnitude is equal to the work done by a unit positive charge to move from point A to point B due to the action of an electric field force, and the direction of the voltage is specified as the direction from the high potential to the low potential. The SI unit system of voltage is volts (V, referred to as volts), and the commonly used units are millivolts (mV), microvolts (V), kilovolts (kv), etc.

This concept is similar to the "water pressure" caused by the high and low water level. It should be pointed out that the term "voltage" is generally only used in electrical circuits, while "potential difference" and "potential difference" are generally applied to all electrical phenomena.

Chinese name voltage.

The foreign name is voltage

Also known as potential difference or potential difference.

Other Definitions. The line-integral symbol u of the intensity of the electric field between two points

The definition is the cause of the formation of an electric current by the directional movement of free charges in a circuit.

Definition of potential difference (voltage difference):

The charge Q moves from point A to point B in the electric field, and the ratio of the work done by the electric field force to the charge quantity Q is called the potential difference between the two points of AB (the difference of the electric potential between the two points of AB, also known as the potential difference), which is expressed by UAB, then there is a formula:

Where, WAB is the work done by the electric field force and Q is the amount of electric charge.

At the same time, it can also be defined in terms of electric potential.

If the magnitude and direction of the voltage do not change with time, it is called a steady voltage or constant voltage, which is referred to as DC voltage, which is represented by the capital letter u. If the magnitude and direction of the voltage change over time, it is called a fluctuating voltage. For circuit analysis, one of the most important fluctuating voltages is the sinusoidal alternating current voltage (abbreviated as alternating voltage), which changes periodically in magnitude and direction according to the sinusoidal law over time.

The instantaneous value of the AC voltage is indicated by the lowercase letters u or u(t). The device that provides voltage in a circuit is a power supply.

This is a simple complex calculation problem for the fundamentals of electricians. If understood in terms of direct current, the inductance is equivalent to the resistance, the voltage and the inductance are known, and if you find the current, then the current = the voltage inductance.

When the pure inductor passes through the alternating current, it can be understood that the inductor should hinder the change of current, that is, when the instantaneous peak of the AC voltage is the maximum, the instantaneous peak of the AC current is the smallest, or the instantaneous peak of the AC voltage is the smallest, the instantaneous peak of the AC current is the maximum, and the AC current lags 90° relative to the AC voltage.

The voltage U=220 2SIN (100T-30°)V, which means that the maximum peak value of the voltage is 220 2, the frequency is 100 Hz, and the initial phase angle is -30°, if it is understood as a direct current with an effective value of 220V, then the current I=220. And because the actual AC current lags by 90°, the actual current is expressed as .

Current i = 1100 2sin (100t-120°).

The vector diagram of voltage and current, expressed in complex numbers, is the simplest, in this case the voltage vector u=220 -30°, and the current vector i=1100 -120°.

The 3A current here has two branches:

One is 2 resistors and the other is.

8 + (40 10) = 8 + 400 50 = 16 So that the 3A current shunt is:

3*16/(2+16)=24/9=8/3a3*2/(2+16)=6/18=1/3a

In this way, the voltage can be known as:

First, divide the current into two branches: one is 2 resistors, and the second is 8+ (40 10'

<> current source outputs electric rolling and Zen flow remains unchanged: Lu Book.

uab = 5 + 2 * 2 = 9v

Writing u is to mark the direction of the dust out, i.e., the voltage polarity, while writing uab already contains the direction.