A girl is standing 150m in front of a tall building, fires a shot with starting pistol. A boy standing 350m behind her, hears two bangs 1s apart. From this information what is speed of sound in air?

300 m/s

Explanation:

The difference in time between the two bangs is 1 s.

Thus;

t2 - t1 = 1

We know that distance/time = speed.

Thus;

d2/v - d1/v = 1

Multiply through by v to get;

d2 - d1 = v

Where v is speed of sound in air.

d1 = 350 m

d2 = (150 × 2) + 350 = 650 m

Thus;

v = d2 - d1 = 650 - 350 = 300 m/s

grav forces affect all objects magnetic forces affect magnetic objects and electric currents

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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