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2 years ago

10

The stoplights on a street are designed to keep traﬃc moving at 26 mi/h. the average length of a street block between traﬃc ligh

ts is about 80 m. what must be the time delay between green lights on successive blocks to keep the traﬃc moving continuously? there are 1.609 × 103 m in a mile. answer in units of s

1 answer:

bonufazy [111]2 years ago

3 0

We use the formula,

$v = \frac{d}{t}$ .

Here, v is velocity and its value given 26 mi/h ( in m/s, $\frac{26 \times 1.609 \times 10^{3} m}{60 \times 60 s} =11.62 \ m/s$ ) and d is distance and its value is given 80 m.

Substituting these values in above formula we get,

$t = \frac{80 m}{11.62m/s } = 6.88 \ s$

Thus, the time delay between green lights on successive blocks to keep the traﬃc moving continuously is 6.88 s

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