To do the experiment, we need to measure about 0.5A current, but there is only one ammeter with 0.3A range in the laboratory If there is 12V power supply, 50 ohm sliding rheostat, resistance wire for electric furnace, wire and switch, how can we temporarily change the range of electric meter to 0.6A? Please draw the circuit diagram and write down the operation steps

To do the experiment, we need to measure about 0.5A current, but there is only one ammeter with 0.3A range in the laboratory If there is 12V power supply, 50 ohm sliding rheostat, resistance wire for electric furnace, wire and switch, how can we temporarily change the range of electric meter to 0.6A? Please draw the circuit diagram and write down the operation steps

The shunt principle of parallel circuit is used
1. Firstly, the sliding rheostat is connected in series with the ammeter and connected to the power supply to calculate the internal resistance of the ammeter
2. Adjust the resistance of the sliding rheostat to the same internal resistance of the ammeter, and then connect it in parallel with the ammeter. At this time, if the current flowing through the internal resistance of the ammeter is 0.3A, then the current flowing through the rheostat is also 0.3A (both have the same voltage, the same resistance and the same current all the time), and the current flowing through the total circuit is 0.6A

When doing electrical experiments, we need to measure about 0.5 a current, but there was only one ammeter with a range of 0.3 A in the laboratory at that time. If we have a 12 V student power supply, a 0-50 ohm sliding rheostat, resistance wire for electric furnace, wires and switches, what simple way can we temporarily change the range of the ammeter to approximately 0.6 a? Draw the circuit diagram and briefly describe the operation steps

The circuit diagram is as follows: operation steps: 1. Connect the circuit according to the diagram, put the slide of the sliding rheostat at the position with the maximum resistance, the switch is in the off state, one end of the resistance wire is screwed on a terminal of the ammeter, and the other end is not connected temporarily; 2. Close the switch, adjust the sliding rheostat, so that the current is expressed to the full scale; 3. Try to connect different positions of the resistance wire to the ammeter To change the length of the resistance wire in the access circuit, when the current is expressed to half bias, screw this position on the terminal. Therefore, when the current is expressed to half bias, the current in the circuit is about 0.6A