As shown in the circuit diagram, the motor and the sliding rheostat are connected in series, the voltmeter measures the voltage at both ends of the motor, and the ammeter measures the current through the motor.
(1) When the car is driving at maximum speed, the cursor is at the far left, and the voltmeter measures the voltage at both ends of the power supply, then the voltage of the power supply. is U;
(2) When the cursor When the chip moves to a certain position A to the right, the voltage representation number is U1 and the current representation number is I1.
∵The total voltage in the series circuit is equal to the sum of the partial voltages.
∴The voltage U across the sliding rheostat = U-U1,
∵The current I everywhere in the series circuit is equal,
∴At this time, the power of the motor and the power consumed by the sliding rheostat Ratio:
| Motor P | Rheostat P |
| U1I1 | U slip I1< /td> |
| U1 |
| UU1 |
Answer: The relationship between power of the motor and the power consumed by the sliding rheostat is
| U1 | UU1 |