- #1
squelch
Gold Member
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Homework Statement
A steel container is completely filled with gasoline, and then sealed. The temperature is then increased 11 degrees C. If the bulk modulus of gasoline is [itex]1.90 \times {10^9}Pa[/itex], find the increase in pressure of the gasoline if:
(a) The expansion of the container is considered.
(b) The expansion of the container is ignored.
(For gasoline, [itex]\beta = 9.60 \times {10^{ - 4}}^ \circ {C^{ - 1}}[/itex])
Homework Equations
[tex]\Delta V = {V_0}\beta \Delta T[/tex]
[tex]p = \frac{F}{A} = - Y\alpha \Delta T[/tex]
The Attempt at a Solution
The volume of the steel container will expand to a final volume:
[tex]{V_c} = {V_0}(1 + {\beta _{(steel)}}\Delta T)[/tex]
Similarly, the volume of the gas expands:
[tex]{V_c} = {V_0}(1 + {\beta _{(gasoline)}}\Delta T)[/tex]
Because we filled the container up to the brim before sealing it, we can assume the initial volumes are equal and that the initial pressure is one atmosphere (how relevant the latter point is I'm not sure). The initial volume isn't given, but I can relate the two ratios:
[tex]\frac{{\Delta {V_s}}}{{{\beta _s}}} = \frac{{\Delta {V_g}}}{{{\beta _g}}}[/tex]
Presumably, the liquid gasoline expands more than the steel canister. I know that pressure = force / area and I know that [itex]p = \frac{F}{A} = - Y\alpha \Delta T[/itex], but I'm not entirely sure how to apply that latter equation to what I know.