What is the function of sliding rheostat in measuring resistance by voltammetry

What is the function of sliding rheostat in measuring resistance by voltammetry

The function of sliding rheostat: 1. Protection circuit
2. Change the voltage in the circuit, so as to change the current in the circuit, get multiple groups of data, calculate multiple groups of electricity
Resistance, find out the average, to reduce the error
(the second is simply to say "average value by multiple measurements to reduce error")

The sliding rheostat changes the current in the circuit by changing the resistance of the part connected to the circuit. Does it change the current of the whole circuit?

Yes, if the current in series is equal everywhere, since the current flowing through the rheostat is changed, the current of the whole circuit will be changed; if it is a parallel circuit, the current of the branch connected to the sliding rheostat will be changed, but the total current of the whole circuit I = u / R, the resistance R is changed, and the current of the whole circuit will be changed

The sliding rheostat changes the resistance by changing the resistance line in the access circuit, so as to change the resistance in the circuit,

The first space is: length, the second space is: current or resistance value

Relationship between sliding direction of sliding rheostat and resistance of access circuit

It's hard to say that it's related to the wiring mode of sliding rheostat. Generally, the middle tap is connected to one end of the two ends. If this part of the resistance is short circuited, the size of the rheostat depends on the size of the other part of the resistance