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Driving a SUV in airless enviroment

  1. Jan 7, 2007 #1
    Imagine driving a hypothetical SUV(or any car for that matter) in an airless environment and assume that you manage to feed oxygen to your engine somehow, would that increase the risk of roll over during a straight-line motion and/or severe braking as the friction is the only force to cause it in the absence of air resistance?
  2. jcsd
  3. Jan 7, 2007 #2


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    Science Advisor

    I can't imagine that air resistance is an important factor in preventing a vehicle from rolling over!
  4. Jan 7, 2007 #3
    same qestion: but driving your land rover with a snorkle in water about 2 m deep.
  5. Jan 7, 2007 #4
    Air drag force is directly proportional to the square of car's speed. Wouldn'T you say that it's a balancing force to the friction's attempt to apply torque at the wheels to twist the the car around its center of mass? Air drag force is also proportional to the area. It's effect is higher above the center of mass than below of the car's front(especially SUVs) thus eliminating the possibility that it's torque effect is balanced.
  6. Jan 7, 2007 #5


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    Drag acts parallel to the direction of motion. Rollover is perpendicular to the direction of motion. The only time rollover depends on air drag is when high winds are involved (and that does happen on bridges every now and then).

    Rollover happens because the cars momentum is going forward while the wheels are trying to turn the momentum to one side. It is that turning force that the momentum is acting against to roll the car over.
  7. Jan 7, 2007 #6
    There's a misunderstanding here probably the blame is on me, I was referring to the roll over that happens on the same way the car travels i.e. car's back is lifted to the air.
    In that case, imagine the torques of the friction force between the wheels and the road and the twist effect they create due to "Level Arm" between them and the center of mass.
    ... and imagine now the air drag force acting on front top of car with a reverse torque effect and that effect can be powerful on high speeds.
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