The speedometer of your automobile shows that you are proceedig at a steady speed of 80 although your automobile is in accelerated motion?

The engine must provide power to compensate friction

Explanation:

Accelerated Motion

Newton's first law states that a body will keep its speed or state of rest while no external net force is applied. Our automobile is running through a road which surface exerts a frictional force on the wheels. If we didn't use fuel, the automobile will eventually stop, because the unbalanced friction force causes deceleration. To compensate that force, we must provide power to the engine. When our speedometer shows a constant speed, the net force is zero, but the car needs to accelerate some, just to compensate the friction force.

The total acceleration keeps being zero, but the engine is actually doing work against friction.