Question

A glass tumbler containing 243 mL of air at 100 k Pa and `20^(@)C` is tuned upside down and immersed in a water bath to a depth of 20.5 metre. The air in the glass is compressed by the weight of water above it. Calculate the volume of air in the glass assuming the temperature and the barometric pressure have not changed.

Answer 1

Correct Answer - `80.7 mL`
Hydrostatic pressure `= h xx d xx g`
`= 20.5 xx 1 xx 9.81`
`201.105 k Pa`
Inside the water bath atmospheric pressure and hydrostatic pressure acts :
`P_("total") = 100 + 201.105 = 301.105 k Pa`
`P_(1) V_(1) = P_(2) V_(2)`
`100 xx 243 = 301.105 xx V_(2)`
`V_(2) = 80.70 mL`