Which wheels will lift in a fast turn?
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Which wheels will lift in a fast turn?
As lunch-time discussions go, this topic generated a lot of participation with no real conclusion at the end.
The question is: If you take a turn going very fast in a car, which wheels will lift off the pavement? The inside wheels or the outside wheels? Would it make any difference if the pavement of the turn is completely flat or if it is banked (in the direction of the turn, of course)?
About half of the people thought the outside wheels will lift (because the car would lean towards the inside in a turn and therefore there is less weight on the outside wheels) while the other half thought the inside wheels will lift (because the momentum for the car is to go straight, if the car loses traction in the turn, the car will roll towards the outside and therefore the inside wheels will be the first to lift).
Are there any physicists out there who can help us answer this question?
The question is: If you take a turn going very fast in a car, which wheels will lift off the pavement? The inside wheels or the outside wheels? Would it make any difference if the pavement of the turn is completely flat or if it is banked (in the direction of the turn, of course)?
About half of the people thought the outside wheels will lift (because the car would lean towards the inside in a turn and therefore there is less weight on the outside wheels) while the other half thought the inside wheels will lift (because the momentum for the car is to go straight, if the car loses traction in the turn, the car will roll towards the outside and therefore the inside wheels will be the first to lift).
Are there any physicists out there who can help us answer this question?
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To me, if you are on flat pavement, the inside wheels will lift in a turn, and if it's bad enough, the car will roll over. I don't know how anyone could think the outside wheels would lift.
Banked turns are banked to keep this from happening, so the wheels don't lift.
Banked turns are banked to keep this from happening, so the wheels don't lift.
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From: Covington WA, USA
Originally Posted by Kyras,Mar 31 2010, 09:03 AM
I don't know how anyone could think the outside wheels would lift.
In this problem, the weight of the car will move to the outside wheels. In the extreme case, the inside wheels will become entirely unweighted. (The suspension complicates the matter somewhat.)
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From: Canton, MA
White,
Let's define our terms. The inside wheels are those closest to the inside of the curve. As you enter the turn, the car leans in the opposite direction (to the outside). So, if you are taking a right hand turn, the car will lean to the left, unloading the tires on the right. When this happens the inside (right side in this case) will be the first side to lift.
The next issue is which lifts first, front or back inside. They usually do not lift together. In my experience, front wheel drive cars will first lift the inside front wheel while rear wheel drive cars will lift the inside rear wheel first. Of course, the springs and shocks may dictate a diffeerent result.
Cars without a locked or limited slip differential will usually fall back down when this happens as power will go to the free wheel and the car will slow down.
Let's define our terms. The inside wheels are those closest to the inside of the curve. As you enter the turn, the car leans in the opposite direction (to the outside). So, if you are taking a right hand turn, the car will lean to the left, unloading the tires on the right. When this happens the inside (right side in this case) will be the first side to lift.
The next issue is which lifts first, front or back inside. They usually do not lift together. In my experience, front wheel drive cars will first lift the inside front wheel while rear wheel drive cars will lift the inside rear wheel first. Of course, the springs and shocks may dictate a diffeerent result.
Cars without a locked or limited slip differential will usually fall back down when this happens as power will go to the free wheel and the car will slow down.
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Originally Posted by mikegarrison,Mar 31 2010, 01:05 PM
I do. Many people rely on "intuitive physics." They think, for instance, that an object being spun around in a circle will move in a circular path if it is suddenly released. (In fact, it will move in a straight path.)...