A person driving her car at 47 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 (Fig. 2-29). The intersection is 15 m wide. Her car's maximum deceleration is -6.2 m/s2, whereas it can accelerate from 47 km/h to 70 km/h in 6.9 s. Ignore the length of her car and her reaction time.(adsbygoogle = window.adsbygoogle || []).push({});

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?

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# Homework Help: Physics question on acceleration

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