Final answer:
Power steering is the system that assists the driver in turning the steering wheel by reducing physical effort, using either a hydraulic pump or an electric motor.
Step-by-step explanation:
The system that provides power assistance when the driver turns the steering wheel is known as power steering. This system can be hydraulic, electric, or a combination of both. Hydraulic systems use a motorized pump to pressurize fluid, which then helps to turn the steering mechanism with less effort from the driver. Electric systems use an electric motor to provide the necessary assistance. In both cases, the power steering system greatly reduces the physical effort required to turn the steering wheel, especially at lower speeds or when the vehicle is stationary.
The relevance of examples such as the dimming of lights when heavy appliances like refrigerators start running, or when a car's engine is started, is that these examples illustrate the concept of electrical load and resistance within a system. When components like the power steering pump or electric motor are activated, they can draw a significant amount of power, which can sometimes be noticed in the form of slight dimming in other electrical components.