The voltage of a certain section of circuit is 120V, and the current flowing is - 2.5A. Do you want to know whether this section of circuit generates power or consumes power? What is the power? I The voltage of a certain section of circuit is 120V, and the current flowing is - 2.5A. Do you want to know whether this section of circuit generates power or consumes power? What is the power? I need it urgently

The voltage of a certain section of circuit is 120V, and the current flowing is - 2.5A. Do you want to know whether this section of circuit generates power or consumes power? What is the power? I The voltage of a certain section of circuit is 120V, and the current flowing is - 2.5A. Do you want to know whether this section of circuit generates power or consumes power? What is the power? I need it urgently

The voltage is positive and the current is negative, which indicates that the current flows from low potential to high potential, so it can be judged as the power generated by "power supply", P = u * I = 120 * 2.5W = 300W

Given the voltage and current, calculate the power

Single phase, resistive load: power = voltage × current
——Single phase and inductive load: power = voltage × current × power factor × conversion efficiency (such as single-phase motor)
——Three phase, resistive load: power = voltage × current × root 3
——Three phase, inductive load: power = voltage × current × root 3 × power factor × conversion efficiency
——5. Two phase 380V power supply equipment: for some equipment, two-phase 380V power supply (i.e. two live wires. For example, two-phase 380V welding machine) is used. Its calculation method is the same as that of single phase, but the voltage is different

Voltage and power in a circuit
"The 100W bulb with rated voltage of 220 V works under 110 V, and its power is only 1 / 4 of the rated power"
Why is this? Please write down the analysis process

P = u * U / R when the resistance is constant, the voltage is reduced by half, and the power is only 1 / 4 of the rated power
Bring in the actual value: 100 = 220 × 220 / r r = 48400 / 100 = 484 Ω
At 110V voltage: P = 110 × 110 / 484 = 12100 / 484 = 25W
25W is one fourth of the original power

Xiaoliang used a 6V power supply and a 2.5V small bulb to test the rated power of small bulb

(1) P=UI
(2) Brief introduction
(3) Small bulb open circuit
（4） B
(5) B, 0.5, 12.5, adjust the voltage of the small bulb
（6） 25