Physics
posted by jenn on .
At 30.0 m below the surface of the sea (density = 1025 kg/m3), where the temperature is 5.00°C, a diver exhales an air bubble having a volume of 0.80 cm3. If the surface temperature of the sea is 20.0°C, what is the volume of the bubble just before it breaks the surface?

Use the combined gas law:
P1*V1/T1= P2*V2/T2 temps in Kelvins.
Pressure 30 m down can be figured this way.
Pressure= weight water above it+ atmospheric
= density*height + atmospheric pressure 
oh yes, multiply the density by the gravational field constant to convert kg to N.
Pressure= density*g*height + atmospheric 
A point source of light is 12 cm below the surface of a large body of water (n=4/3).
What is the radius of the largest circle on the water surface through which the light
can emerge? 
25