Question

While filming an intense action sequence for the next James Bond movie, a controlled explosion detonates 1.3 \({\rm km}\) away from the actors. If the speed of sound through solid rock is 3000 m/s on average, the actors will feel the explosion before they hear it. How much time will pass between when they feel the explosion and when they hear it?

Answer 1

Part A.

time taken by actors to feel the explosion, we know that:

time = distance/speed

t = d/V

V = Speed of sound through solid rock = 3000m/sec

d = distance traveled = 1.3 km = 1300 m

So,

t1 = 1300/3000 = 0.433 m/sec

Now time taken by Sound through air will be:

V = Speed of sound through air = 343 m/sec

d = distance traveled = 1.3 km = 1300 m

So,

t1 = 1300/343 = 3.79 m/sec

So time passed between when they feel the explosion and when they hear it = dt = t2 - t1

dt = 3.79 - 0.433 = 3.357 sec

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