Should the driver make a run for it at an intersection with a yellow light?

AI Thread Summary
The discussion centers on whether a driver should stop or proceed through a yellow light when 30 meters from the intersection, given a 2-second yellow light duration. The car is traveling at 50 km/h, with a maximum deceleration of -6 m/s² and an acceleration time from 50 to 70 km/h of 7 seconds. Key calculations involve determining if the car can stop in time or if it can safely accelerate through the intersection within the yellow light's timeframe. The conversation emphasizes the need for a formula that incorporates initial velocity, distance, and acceleration to make this decision. Ultimately, the driver must analyze the physics of motion to decide the best course of action.
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Homework Statement


A person driving her car at 50km/h approaches an intersection just as the traffic light turns yellow. She knows that the yellow light lasts only 2s before turning red, and she is 30m away from the near side of the intersection. Should she try to stop, or should she make a run for it? The intersection is 12m wide, and her car's max. deceleration is -6m/s^2. Also her car takes 7s to accelerate from 50km/h to 70km/h. Ignore the length of the car and her reaction time.


Homework Equations


I don't know.


The Attempt at a Solution


I don't know. Please help.
 
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First, how much is the acceleration, when we say: if you hit the gas pedal in that car, you can accelerate from 50 to 70 km/h in 7 seconds?

You approach an intersection with a given initial velocity, and you have to cover a given distance, with a certain amount of acceleration. Will 2 seconds be enough time? Look for a formula that includes those variables.
 
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