How Far Will the Spring Compress When the Gas Temperature Rises to 100°C?

  • Thread starter Thread starter mustang06
  • Start date Start date
  • Tags Tags
    Piston Spring
AI Thread Summary
The discussion revolves around calculating the compression of a spring when the gas temperature rises from 20°C to 100°C. The problem involves using the ideal gas law and Hooke's Law to relate pressure, volume, and spring compression. The user has attempted to find the solution but is struggling with unit conversions and setting up the equations correctly. They know the textbook answer is 1.02 cm but need assistance in showing their work. Clarifications on pressure definitions and unit consistency are emphasized as critical for solving the problem accurately.
mustang06
Messages
2
Reaction score
0

Homework Statement


A horizontal piston is attached to a spring with a spring constant of 1500N/m. The cross sectional area of the cylinder is A=10cm^2, it contains 0.0040mol of gas. At 20 deg Celsius the spring is neither compresssed nor stretched. How far is the spring compressed, x, if the gas temperature is raised to 100 deg Celcius?


Homework Equations


PV=nRT ...(P_1 * V_1)/T_1 = (P_2 * V_2)/T_2


The Attempt at a Solution


I assume that the increased volume V_2 = V_1 + Ax. And P_1 is standard pressure, and i need to work in Kelvins, but I have tried everything I know to get the right answer but can not.
I know the answer via the back of our textbook which is 1.02cm. But it is a problem we need to show our work on, and I can't figure this one out. Any help would be greatly appreciated.
 
Physics news on Phys.org
What's the definition of pressure? What would the force applied on the spring be equal to (Hint: Consider Hooke's Law) ?
 
Also be very careful re units--this came up recently in a similar problem, where atmospheres of pressure need to converted to Bars, and volume units made to be the same, eg 1 liter is a 1000cm^3.
JS
 
yeah, Pressure = F/A, and F = -kx => -kx/A must equal the pressure exerted by the spring. I have all my units in Pa, m^3, and K, i really don't know where I am going wrong,
 
last time this came up, the soln was a quadratic, maybe if you posted the completed eqn with all the subs and algebra, we may me able to comment
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top