I didn't explain it well. The laws of aerodynamics are the same for anything.
In engineering, you are always trading off one thing for another. With something like a car, the losses include heat, rolling resistance, aerodynamic sources, drive train losses, and some other factors. The positive factor that overcomes these losses is the power generated by the motor. All types of propulsion have a theoretical maximum efficiency. For an ICE, it varies a bit from engine to engine, but it's somewhere around 35%. That is you put one gallon (33 KWh) of gas through the engine and about 2/3 of it will be lost to heat and mechanical losses within the engine. This is before you try to do any work with the engine. Electric motors can have a theoretical efficiency over 90%.
ICE need to idle because they produce 0 torque at 0 RPM and it takes some time to spin up to a point where it can do any work. So the engine needs to idle when the car isn't moving. This, or course, is all wasted energy. ICE engines achieve their max efficiency at a certain RPM which is different for each engine. Transmissions are designed to keep the engine as close to that sweet zone as possible. One reason car makers are coming out with more and more speeds on transmissions and CVTs are on some cars. ICE cars also need a transmission to increase torque to the wheels at low speeds without overloading the engine and keep it from stalling.
Hybrids further try to eek more out of an engine by keeping the engine running at it's peak efficiency when it's running and to charge the battery if only part of the engine's output is needed for propulsion.
Most ICE cars have their transmission geared to be in the sweet zone of max efficiency somewhere around 60-70 mph. Again it will vary some from car to car, but it's true for most ICE. At those speeds, the aerodynamic drag is a greater factor than at lower speeds, but because the engine is running at it's most efficient mode, the overall efficiency is better at those speeds. If the car was geared to get max efficiency around 25 mph, the gas mileage would be even better if you really wanted to drive on the highway at 25 mph for long distances on a regular basis.
Electric motor cars have different efficiency curves. Most don't have transmissions because the sudden torque changes possible with an EV can rip apart a transmission, and while a transmission might help some, the benefit is nowhere near as great as you get with an ICE. Most EVs have peak efficiency around 25-30 mph. Most of the losses for an EV are rolling resistance and aerodynamic drag. Electric motors are not very efficient at very low speeds, but the efficiency flattens out at relatively low RPMs compared to ICE. This is a complex graph, but it shows the torque vs RPM vs efficiency for an electric motor
View attachment 108945
Even at 200-330 RPM an electric motor can by 75% efficient. Twice the theoretical maximum for an ICE.
At low speeds the car is overcoming rolling resistance. The coefficient of friction is different for a moving object than for a stationary one. If you have ever pushed a heavy object, it was really tough to get going, but much easier to keep moving once it broke free. That the difference between static and dynamic friction.
Anyway, once the car gets moving and the electric motor starts getting up into the 90% efficiency realm, you're moving about 25 mph. There is some aerodynamic drag, but not all that much yet, so the car's efficiency peaks around there. As you get going faster, the aerodynamic drag cuts into your efficiency more and more and there is very little you can do about it, unlike an ICE.
With Teslas people try to hypermile them by driving as close to 25 mph constantly for a full charge to get as much range as possible. Probably everybody here has come close to hypermiling an ICE. Simply fill up the tank and drive at low freeway speeds with cruise control on.
Anyway, that's the long winded answer. Yes aerodynamic drag follows the same laws of Physics on both types of vehicles, but it's a more important factor in an EV design than an ICE design. The same aerodynamic feature will increase gas mileage in an ICE, but what might only improve efficiency 1-2% in an ICE will improve things 5% or more in an EV.
