Yes i can use P1 V1 = P2 V2 (but i guess the air goes away in bubble and not compressed right ?) and no it's not a homework. The answer may be: it will take an infinite time to fill the tank because while we go in depth, the difference of pressure btw the outside and the inside will decrease...
Hey,
Let's imagine I have a tank, filled with air at atmospheric pressure. This tank have a closing/opening valve.
I dive this tank at 100m under water and opened ce valve, my filling speed will be sqrt( 2*g*h) with h=100m.
Now, if i want to dive the tank (with a volume X) continuously at a...