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Anonymous asked in Science & MathematicsPhysics · 1 decade ago

Physics Help ! thank you very much !!?

A person driving her car at 54 km/h approaches an intersection just as the traffic light turns yellow. She knows that the yellow light lasts only 2.0 s before turning to red, and she is 30 m away from the near side of the intersection. The intersection is 15 m wide. Her car's maximum deceleration is -6.0 m/s2, whereas it can accelerate from 54 km/h to 70 km/h in 4.8 s. Ignore the length of her car and her reaction time.

a). If she hits the brakes, how far will she travel before stopping?

b). If she hits the gas instead, how far will she travel before the light turns red?

c). Should she try to stop, or should she speed up to cross the intersection before the light turns red?

___stop ____speed up

1 Answer

  • 1 decade ago
    Favourite answer

    Not using math, but my intuitive senses from driving a car, I think she will be in the intersection before she can stop, and it's best if she just keeps going, even without hitting the gas, but keep foot near brake, and look alert, ready for anything. Other drivers might not be so law-abiding.

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