Recent content by JMatt7

Thank you for your answer! I think I understand now what the author meant. It simply didn't exactly resonate with the concept of statistical ensemble that I have from thermal physics. As you said, astronomers are capable of taking a "snapshot" at the galaxy and determine the position and...

Hi! I'm currently reading "The Virial Theorem in Astrophysics" by G.W. Collins (the book is available as a free web edition at http://ads.harvard.edu/books/1978vtsa.book/) in which the author claims the importance of the ergodic hypothesis when applying the virial theorem to astrophysical...

You're making the assumption that the acceleration is constant during the process, which is unlikely. Try not to assume anything about what happens inside the material, except that all the reaction forces acting on the bullet can be averaged into a single force that slows it down. I'll suggest...

Ahaha. Yes, you're right. Apparently I didn't. So ##I^2Rt = 1200 ~J## and therefore: ##T_{eq} ≈ 326.4~ K## ##ΔU ≈ 982.1 ~J## ##ΔS_{He} ≈ 3.14 ~J/K## ##ΔS_R ≈ 0.7 ~J/K##

Sure. I might have been a bit sloppy with numbers. So using the given data: ##mc = 10 g ~ 0.2~ \frac {cal} {K~g} = 2~ \frac {cal} K ## ##nc_v = 3~ mol~ \frac {3}{2}~ R = 3~mol~ \frac {3}{2}~ 1.987~ \frac {cal}{K ~mol} ≈ 8.94 \frac {cal} K## Therefore, since ## 1 ~cal = 4.18 ~J##: $$T_{eq} =...

(I'm going to assume that the wheelbarrow is standing on the ground, and therefore the force acting in A is the reaction force from the ground) First of all, if you want to apply the torque equation you have to choose a pivot point and then calculate the torques relative to that point. The...

Homework Statement A current ## I=0.2 A ## flows in a resistor ##R = 50 Ω## immersed in a rigid adiabatic vessel that contains ##n=3## moles of Helium. The initial temperature of the system is ##T_0 = 27 °C##. The resistor has a mass ## m = 10 g## and specific heat ## c = 0.2 (cal/K)/g ##...