In the microscopic expression of the current, that is, the determinant: I = nqsv How to understand it? I don't understand the number of charges per unit volume I misunderstood the number of free charges and the quantity of charge

In the microscopic expression of the current, that is, the determinant: I = nqsv How to understand it? I don't understand the number of charges per unit volume I misunderstood the number of free charges and the quantity of charge

Current = number of charges per unit volume × electric quantity of unit charge × cross-sectional area of conductor × charge velocity
The so-called: the number of charges per unit volume is that n charges can be contained in the conductor per unit volume
It's like a box of 1m and 179; that can hold n small balls

Current intensity formula
The formula is I = q / T. what do Q and t represent?

Q stands for electricity quantity
T is time
If you think of the current as water flow, you can get the "water quantity" of Q after a period of time t, so OK,

What is the formula of high school physics output power
For non pure resistance circuit, is the output power UI or I & # r

Whose output power, if the output power of the power supply is UI, that is, the product of the terminal voltage and the main circuit current, if it is the mechanical output power in the non pure resistance circuit, it is = the voltage at both ends of the electrical appliance multiplied by the current - the heating power of the machine (I & # 178; R)