Answer:
529 Hz
Explanation:
595(343-20)/(343 + 20) = 529
The megaphone is cupping the area around her mouth and it is like with your hands, if you cover around them the noise will be louder. It is because it is hollow and there isn't anything to block the noise through the megaphone.
Answer:
J = 14.4 kg*m^2
Explanation:
Assuming that the wheel is not moving anywhere, and the kinetic energy is only due to rotation:
Ek = 1/2 * J * w^2
J = 2 * Ek / (w^2)
We need the angular speed in rad / s
566 rev/min * (1 min/ 60 s) * (2π rad / rev) = 58.22 rad/s
Then:
J = 2 * 24400 / (58.22^2) = 14.4 kg*m^2
Answer:
electromagnetic waves only
Explanation:
I just took the test, Hope it helps!
I believe the correct answer is expansion.
