Why does a small lightweight car generally have a better fuel economy than a big heavy car?

Question

how does a streamlined design improve fuel economy?
engine

Answer 1

F=ma Force = Mass x acceleration. The heavier car has more mass and takes more energy to accelerate. Every time you accelerate, the heavier car is going to use more fuel than the lighter car.

Answer 2

simply put it as a heavier car needed more power to move and thus the higher fuel comsumption.
Big heavier cars usually have a higher engine capacity and more cylinder number in engine.This is to carry the weight of the car itself. The higher = lower the fuel comsumption.

Then again it also depends on the way you drive.

A streamlined design help improve fuel economy by reducing opposing forces. When you are traveling at high speed, the wind blowing towards you actually slows you down causing the car to use more energy to move forward. Streamlined design will actually reduce opposing wind forces and also reducing the engine load. Thus improving fuel economy

Answer 3

May reasons, but here are a couple....

-- The heavier a car is, the more powerful the engine needs to be to make it move; more power means more gas is needed.
-- Lighter cars have samller engines, as they do not need to be as powerful; less gas is used as a result

A streamlined design can imrove fuel economy because there is less resistance on the car when driving ("cuts" through the air better), which results in less gas being used to maintain speed or accelarate; the higher the amount of resistance on the front of a car when driving, the more gas it takes to make it move against that resistance. Example: on a windy day, it takes less effort to walk against the wind when pointing an umbrella forward than it does when holding a cardboard box; less surface area = less resistsnace = less gas use :)

Answer 4

It is observed that car consumes fuel for moving itself.more heavy is the car more fuel is consumed and viceversa.so light cars are fuel efficient.streamlined cars face less air resistance so they move with less atmoshpheric friction consuming less fuel to move...

Answer 5

they have a smaller engine,like a v8 is harder on gas than a 4 cyclinder and the more weight of the car the more gas is used