How is it much more fuel efficient to travel at say 50 mph for longer than 70 mph for a shorter period of time. Like if I was going a set distance, if I drive slower I’m using the car longer so why isn’t it the same fuel being used.

Question

How is it much more fuel efficient to travel at say 50 mph for longer than 70 mph for a shorter period of time. Like if I was going a set distance, if I drive slower I’m using the car longer so why isn’t it the same fuel being used.

In: 15

Answer 1

Eli5 version.

Walk a block. Takes some energy not a lot.
Now run a block. Goes quicker, but you’re breathing harder right?
It’s like that.