Prediga la velocidad en A 2 si el área de A 2 es la mitad del área de A 1 y la velocidad en A 1 es de 2
m/s.

massxgravity x heght=weightxheight= pe

4900=490xh

h=10

wavelength divides in half and speed stays the same.

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me