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Old 03-30-2011, 12:23 AM   #10 (permalink)
roflwaffle
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Quote:
Originally Posted by orange4boy View Post
I have a question (sort of related to this thread)

In theory, assuming zero drag, does it consume more energy to accelerate quickly to X speed or slowly to X speed. The final kinetic energy is the same so if there are losses where do they go? Is the energy required to accelerate an exponential curve with greater requirements for faster acceleration? My understanding is that it's the same total energy to get an object to X speed but since it's over time then to accel to the same speed in half the time requires the same amount of energy twice as fast.

Am I on the right track here or is my grasp of physics slipping?
That depends on how quickly. Like OM and dave mentioned, the most efficient engine operation happens at about three quarters of full load from ~2000 to ~3000 rpm depending on the engine.

In terms of the calculator, there is a path that optimizes acceleration and fuel efficiency, but in practice that depends on the transmission specifics, especially for automatics, but also for manuals since they both have different efficiency curves compared to engines or the type of transmission used for SAE testing.
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