In the experiment of measuring resistance by voltammetry, sliding rheostat has () A. Change the current in the circuit B. change the voltage at both ends of the measured resistance C. change the resistance value of the measured resistance D. protect the circuit

A. Moving the slide of the sliding rheostat changes the resistance connected to the circuit and the current in the circuit, which is in line with the theme. B. in the experiment, the resistance value of the resistance does not change. Moving the slide of the sliding rheostat changes the current in the circuit. According to u = IR, the resistance does not change, the current changes, so the voltage changes at both ends of the measured resistance

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