X-Git-Url: https://hackdaworld.org/gitweb/?a=blobdiff_plain;f=solid_state_physics%2Ftutorial%2F2_02.tex;h=b9b5c5a93af222bb4722c4d5382faceb861b7866;hb=fec7e52be07515b5dac392facfa0b2022d002c21;hp=8787db56333869653cc81eae8062045268410611;hpb=82e203acc6d8f125b12df53e5697d5df0875f0e3;p=lectures%2Flatex.git diff --git a/solid_state_physics/tutorial/2_02.tex b/solid_state_physics/tutorial/2_02.tex index 8787db5..b9b5c5a 100644 --- a/solid_state_physics/tutorial/2_02.tex +++ b/solid_state_physics/tutorial/2_02.tex @@ -56,9 +56,10 @@ and $\lambda$ is the London penetration depth. of the wire. Assume, that the penetration depth $\lambda$ is much smaller than the radius $R$ of the cylinder. {\bf Hint:} - Use the relation $I_c=\int_0^R dr \int_0^{2\pi} d\phi \, j_c(r)$ + Use the relation $I_c=\int_0^R dr \int_0^{2\pi} d\phi \, j_c(r) r$ and integration by parts. - \item Calculate $j_c(R,T=0K)$ for a wire of Sn with a radius of 1 mm at $T=0K$. + \item Calculate $j_c(R,T=0K)$ for a wire of Sn with a diameter of 1 mm + at $T=0K$. The critical current and penetration depth at $T=0K$ are $I_c=75\, A$ and $\lambda =300\cdot 10^{-10}\, m$. \end{enumerate}