Answer:
20 metres
Explanation:
<em>Speed</em><em> </em><em>=</em><em> </em><em>distance</em><em> </em><em>÷</em><em> </em><em>time</em>
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If we substitute the values:

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Answer:The disturbance created by a source of sound in the medium travels through the medium and not the particles of the medium
Explanation:i hope this is right
Answer:
0.1111 W/m²
Explanation:
If all other parameters are constant, sound intensity is inversely proportional to the square of the distance of the sound. That is,
I ∝ (1/r²)
I = k/r²
Since k can be the constant of proportionality. k = Ir²
We can write this relation as
I₁ × r₁² = I₂ × r₂²
I₁ = 0.25 W/m²
r₁ = 16 m
I₂ = ?
r₂ = 24 m
0.25 × 16² = I₂ × 24²
I₂ = (0.25 × 16²)/24²
I₂ = 0.1111 W/m²
Index of refraction of a substance =
(speed of light in vacuum) / (speed of light in the substance)
Index in quartz = (2.9979 x 10⁸ m/s) / (2.0567 x 10⁸ m/s)
<em>Index = 1.4576 </em> (no units)
A descriptive observation may very well be a mixture of both quantitative and qualitative as it can utilize elements of both types. Qualitative deals with the kinds of observations that cannot be measured in numerical form. Quantitative data is just that.