Two containers are at the same temperature. the first
containsgas with pressure p1,molecular
mass m1,and
root-mean-square speed vrms1.the
second contains gas with pressure 4p1,molecular
mass m2,and
average speed vavg2=
5vrms1.find
the mass ratio m1/m2.

From Maxwell-Boltzmann distribution of molecules and their speeds,

average speed, Vavg = √()

and Root mean speed, Vrms = √()

Given Vavg2 = 5Vrms1

Vavg2 = √() ................ eqn 1

Vrms1 = √() --------------eqn 2

To find m1/m2, we divide eqn 1 by eqn 2,

we have, Vavg2/Vrms1 = √()

since Vavg2 = 5Vrms1, it becomes, 5 = √()

Therfore, m1/m2 = 25 * 3π/8 = 29.45

the mass ratio m1/m2 = 29.45.

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