Question

Water expands when heated. Suppose a beaker of water is heated from 10℃ to 90℃. Does the pressure at the bottom of the beaker increase, decrease, or stay the same? Explain.

Answer 1

The Pressure Increases

Explanation:

• When the water is heated from 10℃ to 90℃ the pressure at the bottom of the beaker will also increase.

• For a closed system with liquid contents that is water, the pressure will always increase with a rise in temperature.

       By using the formula;  

      $\frac{P_1V_1}{T_1}= \frac{ P_2V_2}{T_2}$

       where,

      V1 & V2 are the volumes at the initial level and final level, both the volumes are the same(ignoring pressure distention), T1 & T2 are the temperatures and   P1 & P2 are the pressures.

      Therefore, we get the pressure excluding the volumes as -

     $P_2 =\frac{T_2P_1}{T_1}$

• Hence, according to the above explanation, if the temperature of the water increases then the pressure at the bottom of the beaker is also increased.