This is the complete title: During the movement of slide P of rheostat R0, the indication range of voltmeter is 0-4V, and the indication range of ammeter is 0.5-1A. Calculate the organization of resistor R, the maximum resistance of rheostat R0 and the power supply voltage U

This is the complete title: During the movement of slide P of rheostat R0, the indication range of voltmeter is 0-4V, and the indication range of ammeter is 0.5-1A. Calculate the organization of resistor R, the maximum resistance of rheostat R0 and the power supply voltage U

The indication of the voltmeter may be 0, so it measures the voltage at both ends of the resistor. When the indication of the voltmeter is 0V, the rheostat is equivalent to not connected, and the current is 1a. When the indication of the voltmeter is 4V, the resistance of the rheostat connected to the resistor is the maximum, the current is 0.5A, and the power supply voltage does not change, indicating that the resistor R = the maximum resistance of the rheostat R0