Reducing Speed in Towns: Kinetic Energy, Friction, & Work

AI Thread Summary
Reducing speed in towns is crucial due to the high kinetic energy of vehicles, which requires more work to stop suddenly. At higher speeds, the frictional force becomes insufficient to halt the vehicle quickly, increasing the risk of skidding. Proper braking techniques are essential; if a driver brakes too hard, the wheels can lock, causing the car to slide rather than stop immediately. Therefore, maintaining lower speeds in pedestrian areas minimizes the potential for accidents and enhances safety. Overall, slower speeds allow for better control and reaction times in urban environments.
pinkyjoshi65
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why it is necessary to reduce speed in towns or areas with pedestrians compared to a fast highway.

We have to use concepts of Kinetic energy, frictional force and work to figure out the answer..

So..if a person is traveling at a high speed (hence the Kinetic energy is high) in a town, then he will have to do more work to stop the car suddenly. Anyone willing to add in..?
 
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Frition is the force opposing the motion of the car. So when the car is brought to a stop, only friction acts on all the tires, since the foot frm the accelerator is removed. This should be done properly since for a given speed of the car, the wheels need to rotate at a particular rate if the car is not to skid.In other words, if a driver jams on his brakes so that the wheels stop turning too quickly then the car will not come to a halt at the instant that the wheels stop but the car will slide across the surface of the road for a while. Hence it is best that the car is moving at a slow speed. This is what i could get out of this..
 

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