Control variable method (control resistance)

When the resistance is constant, the greater the voltage, the greater the current, and the current is proportional to the voltage.

protect the circuit

Change the resistor voltage and conduct multiple tests

Look for general rules and avoid chance

Control variable method (control voltage)

When the resistance is constant, the greater the voltage, the greater the current, and the current is proportional to the voltage.

protect the circuit

Control the resistor voltage and conduct multiple tests

Look for general rules and avoid chance

Resistor value is constant: current is proportional to voltage

protect the circuit

Change the resistor voltage and conduct multiple tests

Find the average and reduce the error

The resistance value of the small light bulb is not constant: the higher the temperature, the greater the resistance.

protect the circuit

Vary the bulb voltage and perform multiple experiments

Looking for general rules, the relationship between light bulb resistance and temperature

P=UI

The greater the actual electrical power of the small light bulb, the brighter the light bulb will be

protect the circuit

Vary the bulb voltage and perform multiple experiments

Looking for general rules, the relationship between the actual electric power of the light bulb and the brightness