When Xiao Ming was studying in front of a desk lamp at night, he felt very hot and turned on the air conditioner.

Because all the electrical appliances in the home circuit are connected in parallel (1), when the air conditioner is turned on at night, the resistance of the electrical appliances becomes smaller (1), the current in the circuit becomes larger, the voltage at both ends of the line becomes larger (1), and the voltage at both ends of the electrical appliances becomes smaller (1). The power of electrical appliances is reduced, so the lights are dimmed (1 min).