Can a plasma propulsion engine be used to drive cars on earth?

Maybe, but it doesn't really make sense. Plasma propulsion engines work well in space because there reactive mass is extremely limited. read more

Plasma propulsion engines work well in space because there reactive mass is extremely limited. These engines are therefore very efficient in how they use reactive mass to move the spacecraft around, but VERY inefficient in how much energy they need to do so. They're also VERY weak. A car on Earth has the opposite requirements. read more

Basically, propulsion works by throwing stuff, usually hot gases, out of the back of something like a rocket or jet airplane that you are trying to speed up. read more

Moreover, interest is growing also in using plasma as a conductive medium to radiate or reflect EM waves in antenna, referred to as “plasma antennas”. Of course plasma is used also for propulsion, but its applications are restricted to space propulsion, because a plasma engine can’t properly work within the atmosphere. read more

For example, the space shuttle's main engines have a power density of about 70 lbf/lb (70 pounds of force per pound) which means that for each pound of the engine it can lift 70 times its weight. On the other hand, the entire ion propulsion in DS1 can produce 92 mN of force which is "roughly" equivalent to the pulling power of a large beetle, like a cockroach, and DS1 weighs 489.5 kg. read more