How Does a Frictionless Piston Behave in a Vacuum-Sealed Cylinder?

  • Thread starter Thread starter itr
  • Start date Start date
AI Thread Summary
A frictionless piston in a vacuum-sealed cylinder experiences equilibrium when the gas pressure below it balances the weight of the piston. Boyle's law relates the pressure and volume of the gas, allowing for the derivation of the restoring force when the piston is displaced. The motion of the piston can be described by a differential equation that accounts for small displacements around its equilibrium position. The angular frequency of oscillation, omega, is shown to be independent of the mass of the piston. For a container volume of 2000 liters and a cross-sectional area of 1E-4 meters squared, omega can be calculated based on these principles.
itr
Messages
43
Reaction score
0
A frictionless piston of mass m is at a precise fit in the vertical cylinder neck of a large container of volume V. The container is filled with a gas and there is a vacuum above the piston. THe cross sectional area of the neck(and thereby the piston) is A.
a) Derive an equation for the pressure of the gas in the container when the piston is in equilibrium.
b) Assuming that the pressure and volume of the gas are related by boyle's law, derive an equation for the restoring force on the piston when it is displaced by a small amount of x.
c) assuming that the motion of the piston is small enough for boyle's law to be valid, obtain the differential equation for small displacements of the piston about its equilibrium position.
d) show that the angular frequency of oscillation, omega, is independent of m.
e) calculate omega for V=2000 liters and A= 1E-4 meters squared.


I am not to sure where to begin...I know boyle's law is PV = k where...

P denotes the pressure of the system.
V is the volume of the gas.
k is a constant value representative of the pressure and volume of the system

If you could help me in a direction to go that would be great thank you
 
Physics news on Phys.org
does anyone know what to do?
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top