I have seen some Tesla Model 3s with a "Dual Motor" badge. Does it mean those models and other electric vehicles (EVs) without this label have only one motor? What is the advantage of having two motors?

The Tesla models without the Dual Motor badge have only one motor driving the rear wheels. While many EVs are either front- or rear-wheel driven, several manufacturers offer EVs with two motors. Audi even has a model with three motors.

The big advantage of twin-motors is the ability to provide drive to both front and rear wheels, making them effectively all-wheel-drive vehicles.

In an EV, where power distribution between front and rear wheels is controlled by computers, such a system is significantly superior compared with all-wheel-drive systems in combustion-engined cars.

Although many of the latest all-wheel-drive systems in combustion-engined cars rely on electronics to manage power distribution, the active device is a mechanical element (such as a multi-plate clutch), while a single power unit (the engine) transmits power through mechanical means.

With electric all-wheel-drive cars, the motors are individually controlled and power output to the wheels does not require any mechanical means.

Also, an electric motor's inherent characteristic of producing a steady, constant torque is a major factor in enabling discrete and accurate control of power output. This means that the power distribution between the axles is far more precise, with reactions to road conditions which are faster than conventional systems.