• Support PF! Buy your school textbooks, materials and every day products Here!

A vertical cylinder fitted with a heavy leak-proof piston wi

  • #1
1
0

Homework Statement


HERE IS THE QUESTION
A vertical cylinder fitted with a heavy leak-proof piston with diameter 84.0 mm contains air (under the piston) of density 1.59 kg/m3 in thermodynamic equilibrium with the surrounding atmosphere, which is at 100 kPa and 39 oC. Determine the mass of the piston in kg, to three significant figures. Use gravitational constant g = 9.81 m/s2.[/B]



Homework Equations


i tried to use PV=mRT for the air in the cylinder[/B]


The Attempt at a Solution


mg= PA
I know there is a force due the the piston and the force due to the air
FPISTON = FAIR
FPISTON = mg
FAIR THIS IS WHERE IM STUCK IM NOT SURE IF MY WHOLE LOGIC FOR THIS QUESTION IS CORRECT. YOUR HELP IS GREATLY APPRECIATED[/B]
 

Answers and Replies

  • #2
Delta2
Homework Helper
Insights Author
Gold Member
2,423
683
I am a bit confused by your naming/labelling of the forces and the equations you write.

To clear this :
There are three different forces that are acting on the piston. Which are these three forces?
 

Related Threads on A vertical cylinder fitted with a heavy leak-proof piston wi

  • Last Post
Replies
16
Views
3K
Replies
1
Views
3K
  • Last Post
Replies
7
Views
6K
Replies
4
Views
1K
Replies
10
Views
7K
  • Last Post
Replies
11
Views
998
Replies
12
Views
3K
Replies
3
Views
5K
Replies
8
Views
4K
Top