If you and the source of sound are moving apart, then the pitch (frequency) <em>you hear</em> is <em>lower</em> than the pitch (frequency) that's actually leaving the source.
It doesn't matter whether you or the source is the one moving, only that the distance between you is increasing.
Answer:
a
Explanation:
as the copper wire is very dangerous so now if these two thing happens then it would easily help the current flows through it so it might be a little bit easy for the current to flow through it
(C) the government agency that regulates these types of chemicals
Answer:
2513.6 W
Explanation:
Acoustic power = sound intensity × area of hemisphere
Sound intensity = 1 W/m^2
Area of hemisphere = 2πr^2 = 2×3.142×20^2 = 2513.6 m^2
Acoustic power = 1 W/m^2 × 2513.6 m^2 = 2513.6 W