Ask Physics Measuring the electrical power of a small light bulb Detailed experimental steps Urgent

1. First design the experimental circuit, draw the experimental circuit diagram, and design the table used for experimental records. Connect the various devices according to the circuit diagram

2. Check the experimental circuit. After confirming that it is correct, close the switch S, slowly move the slider P of the sliding rheostat, and pay attention to the indication of the voltmeter. When the indication of the voltmeter When the number is equal to the rated voltage of the small bulb, stop moving the slider of the sliding rheostat and record the reading on the ammeter. Substitute the voltage and current values ??into the formula P=UI to calculate the rated power of the small light bulb.

3. Continue to slowly adjust the slider P of the sliding rheostat so that the voltage at both ends of the small bulb is approximately 1.2 times the rated voltage. Observe the brightness change of the small bulb, and note the indications of the voltmeter and ammeter. Substitute the voltage and current values ??into the formula P=UI to calculate the actual power of the small light bulb at this time.

4. Continue to slowly adjust the slider P of the sliding rheostat so that the voltage at both ends of the small bulb is approximately 0.8 times the rated voltage. Observe the brightness change of the small bulb and note down the indications of the voltmeter and ammeter. Substitute the voltage and current values ??into the formula P=UI to calculate the actual power of the small light bulb at this time.

5. Organize experimental equipment. Turn off the switch and remove the wires. Arrange experimental equipment neatly.

Physics Science Network-Experimental measurement of the electrical power of a small light bulb?