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Old 07-23-2013, 12:15 PM   #38 (permalink)
BigWu
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Energy required at the wheels is equal

Quote:
Originally Posted by Maury Markowitz View Post
Sorry, this is not correct. There is no relation between force and fuel use.

Perhaps I should have mentioned I'm a physicist. Because I am :-)
Clarification: The amount of energy expended at the wheels to accelerate to a given speed is identical (assuming you're not burning rubber on the launch). However, in an internal combustion powered car, the efficiency of the engine in converting fuel to usable wheel power varies. Optimal MPG therefore depends on accelerating at the rate of maximum engine and transmission efficiency.

For an electric car it's simple. The energy expended has zero relation to the rate of acceleration.

Ex: If you drive a distance of one mile with a maximum speed of 40 MPH, the total energy consumed will be ~300 watt hours regardless of if you accelerate to 40 MPH in glacial 30 seconds or in just 3. Note that I have confirmed this countless times in my Tesla S.
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