Aroad runs midway between two long parallel rows of buildings .a motorbike moving with a speed of 36 kmph sounds the horn and hears the echo one second after he sounded the horn. the velocity of sound of that day in air was 347.65 m/s calculate the distance between the two rows of bulidings

347.51 meters

Explanation:

When the motorbike sounds the horn, a sound wave moves away from the motorbike, reflects off the buildings at an equal angle, and returns to the middle of the road where it is heard by the driver.

The path taken by the sound wave and the path taken by the motorbike form an isosceles triangle.  The height of this triangle is half the width between the buildings.  So we can use a little geometry to find the answer.

First, let's convert the motorbike's speed to m/s:

36 km/hr × (1000 m / km) × (1 hr / 3600 s) = 10 m/s

So after 1 second, the driver has moved 10 m.  The sound wave moves a total distance of 347.65 m, so each leg of the triangle is half that, or 173.825 m.

Now we can use trig to find the height of the triangle:

h² + 5² = 173.825²

h = 173.753

So the distance between the buildings is:

2h = 347.506

Rounding to two decimal points, the distance between the two rows of buildings is 347.51 meters.

hi there!

out of the two, (b) precision would be more reasonable.   however, both a and b could be pretty reasonable.

-awesomerepublic   : )

see earlier