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

3 0

3 years ago

A student weighing 120 lbs climbs a 12 ft flight of stairs in 9 seconds. how much power did the student create?

Alex Ar [27]

Power can be calculate through the equation,
Power = Force x velocity

It should be noted that velocity is calculated by dividing displacement by time. Thus, from the given in this item we can calculate for the power.
Power = (120 lb) x (12 ft/9 s)
 Power = 160 lb.ft/s

7 0

3 years ago

Which statements correctly describe the properties of air? Select three options. Air has mass but no weight. Air pressure is cre

jolli1 [7]

Answer:

2,4,5

Air pressure is created by the weight of the atmosphere pushing on Earth’s surface.

Denser air is heavier than less dense air.

Air is less dense at higher altitudes.