# Weight of a piston

james brug

## Homework Statement

A vertical cylindrical tank contains 1.80 mol of an ideal gas under a pressure of 1.05 atm at 22.0$$^\circ$$ C. The round part of the tank has a radius of 10.0 cm , and the gas is supporting a piston that can move up and down in the cylinder without friction.

What is the mass of this piston?

pV=nRT

## The Attempt at a Solution

$$.05*1 \; atm*.01\pi \: m^2/9.8 \approx 16.2 kg$$

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## Homework Statement

A vertical cylindrical tank contains 1.80 mol of an ideal gas under a pressure of 1.05 atm at 22.0$$^\circ$$ C. The round part of the tank has a radius of 10.0 cm , and the gas is supporting a piston that can move up and down in the cylinder without friction.

What is the mass of this piston?

pV=nRT

## The Attempt at a Solution

$$.05*1 \; atm*.01\pi \: m^2/9.8 \approx 16.2 kg$$
What determines the pressure of the gas in the cylinder? How much of that force (per unit area) is due to the weight of the pistion?

AM