Question

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

Answer 1

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