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aleksandrvk [35]

3 years ago

13

On February 15, 2013, a superbolide meteor (brighter than the Sun) entered Earth's atmosphere over Chelyabinsk, Russia, and expl

oded at an altitude of 23.5 km. Eyewitnesses could feel the intense heat from the fireball, and the blast wave from the explosion blew out windows in buildings. The blast wave took approximately 2 minutes 30 seconds to reach ground level. (a) What was the average velocity (in m/s) of the blast wave? (Enter the magnitude.) x m/s (b) Compare this with the speed of sound, which is 343 m/s at sea level. Volast wave = sound

1 answer:

fredd [130]3 years ago

7 0

Answer:

156.67 m/s

0.45676 times the speed of sound

Explanation:

Distance from the ground = 23.5 km = 23500 m

Time taken by the blast waves to reach the ground = $2\ minutes\ 30\ seconds=2\times 60+30=150\ s$

Spedd of the wave would be

$Speed=\dfrac{Distance}{Time}\\\Rightarrow v_b=\dfrac{23500}{150}\\\Rightarrow v-b=156.67\ m/s$

The velocity of the blast wave is 156.67 m/s

v = Velocity of sound = 343 m/s

$\dfrac{v_b}{v}=\dfrac{156.67}{343}\\\Rightarrow v_b=v\dfrac{156.67}{343}\\\Rightarrow v_b=0.45676v$

The blast wave is 0.45676 times the speed of sound

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Now we can use equation (2) to find the speed in the lower section:

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$r_1=0.03 cm$

$v_1=0.638 m/s$

Therefore, the volume flow rate is

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