Watkins Glen Cayman Interseries crash at Connecticut PCA DE
#197
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actually if your car is sliding on the track, leaves the track and hits wet grass it will pick up speed (yes it will). I have unfortunately had this happen avoiding a spinning car on a drying track and when I looked the data trace it sure did happen.
#199
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You will have less deceleration on the grass, and therefore it seems like the car is speeding up. The velocity vector of the center of mass will not increase without power being supplied to accelerate the car.
#200
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As sundog suggests, even wet grass has friction so the car will continue to slow down, so the car cannot pickup speed unless their is enough slope for gravity to overcome the friction from the grass. Simple physics really....
Scott
Scott
#201
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Just remember that a spinning car is not simple physics. And I'd bet that bobt993 is talking about actual data when he mentions something that shows a speed increase.
#202
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#203
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It is different. Think about how the speed of the spin could increase and work backwards towards what if the speed of the spin decreased....
#204
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I tried to arrest this by sending a PM. Linear velocity is handled different than angular velocity where you must factor in the physical radius. V is proportional to the R. Cars go off tracks in corners where they are using grip along a radius to move forward (hopefully). If you go straight off after locking up your brakes that is a different situation and not what I encountered. My car swerved avoiding a spinning car then continued into a very wet corner where the car lost grip from leaving the track prior. The once loss of asphalt lat grip to now grass (which is less than half that of asphalt when wet) changed the corner radius slide I attempting to stay on. " R" basically went to infinity and ended at a guard rail.
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#205
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#206
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I tried to arrest this by sending a PM. Linear velocity is handled different than angular velocity where you must factor in the physical radius. V is proportional to the R. Cars go off tracks in corners where they are using grip along a radius to move forward (hopefully). If you go straight off after locking up your brakes that is a different situation and not what I encountered. My car swerved avoiding a spinning car then continued into a very wet corner where the car lost grip from leaving the track prior. The once loss of asphalt lat grip to now grass (which is less than half that of asphalt when wet) changed the corner radius slide I attempting to stay on. " R" basically went to infinity and ended at a guard rail. ![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
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It is impossible to accelerate by going off into wet grass unless you either hit the gas or go downhill. Data may have showed an increase in velocity which was a result of one of the other two scenarios.
Rate of deceleration will be less, sure. Acceleration? No. That would be defying laws of physics.
#207
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Bob, I agree with you on many things, but this one I dont. You cant introduce more forces than you had before.
It is impossible to accelerate by going off into wet grass unless you either hit the gas or go downhill. Data may have showed an increase in velocity which was a result of one of the other two scenarios.
Rate of deceleration will be less, sure. Acceleration? No. That would be defying laws of physics.
It is impossible to accelerate by going off into wet grass unless you either hit the gas or go downhill. Data may have showed an increase in velocity which was a result of one of the other two scenarios.
Rate of deceleration will be less, sure. Acceleration? No. That would be defying laws of physics.
I think were arguing two sides of a coin. My point is leaving a track onto a wet surface and losing the forward motion leaving the corner the car does pick up speed in the direction you want least (towards the wall). The sensation is the car is accelerating just not in the direction you wanted (you have traded cornering speed for a very fast slide in one direction). You are losing one vector of your course direction and exchanging angular velocity for a somewhat larger radius towards a very hard surface.
#210
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I think were arguing two sides of a coin. My point is leaving a track onto a wet surface and losing the forward motion leaving the corner the car does pick up speed in the direction you want least (towards the wall). The sensation is the car is accelerating just not in the direction you wanted (you have traded cornering speed for a very fast slide in one direction). You are losing one vector of your course direction and exchanging angular velocity for a somewhat larger radius towards a very hard surface.
"actually if your car is sliding on the track, leaves the track and hits wet grass it will pick up speed (yes it will)."
That statement is false. The direction can change, but the speed does not increase. In fact, it is always decreasing.
This link explains the feeling of acceleration:
http://courses.ncssm.edu/aphys/labs/elab1/jerk.html
Scott