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14ever1
Jun 7, 2012, 09:05 PM
Here's the question-I don't know how to use a cubed sign so I'll just write: (cubed) next to it or if it's a power I'll write (to the fifth power, etc).

The liquid in the tube has a density of 1.48 g/cm(cubed). The atmospheric pressure is 1.013 X 10(to the fifth power) newtons per square meter. What is the pressure P in the container?

Please show the different steps as you work through them, thank you.

ebaines
Jun 8, 2012, 07:12 AM
The convention for showing powers is to use the carat symbol: ^. Thus cm^3 is "centimeters cubed" and 10^5 means "ten to the fifth power."

The pressure due to the liquid is equal to its density multiplied by the depth of the liquid in the tube. As for atmospheric pressure - it presses down on the top of the liquid and thus adds to the overall pressure. However, depending how the tube is constructed an equal and opposite atmospheric pressure operates upward on the bottom of the tube, canceling out the effect of the pressure acting downward. I suppose for this problem they want you to include the atmospheric pressure anyway.

When you add these two pressure be sure to convert to common units such as N/m^2.