Find the current produced at room temperature in a pure germanium plate of area  2×10−4m2 and thickness is 1.2×10−3 m when a potential of 5 V is applied across the faces. Concentration of carriers in germanium at room temperature is 1.6×106 m−3 . The mobilities of electrons and holes are 0.4m2v−1s−1 and 0.2m2v−1s−1 respectively . The heat generated in the plate in 100 second is

ne=nh=1.6×106 m−3t = 100 SecA=2×10−4m2d=1.2×10−3 mV=5voltμe=0.4m2v−1s−1μh=0.2m2v−1s−1H = ?H = V i t             H = V J A t            (∴i=JA)  H=VσEAt      (∴J=σE)H=V(σe+σh)EAt(∴σ=σe+σh)H=V(neeμe+nheμh)EAt   (∴σ=nμe)      H=Ve(neμe+nhμh)EAtH=Ve(neμe+nhμh)VdAtH=5×1.6×10−19(1.6×106×0.4+1.6×106×0.2)51.2×10−3×2×10−4×100H=5×1.6×10−19×1.6×106(0.4+0.2)51.2×10−3×2×10−4×100          H=5×1.6×1.6×0.6×51.2×2×10−14×100H=6400×10−14H=6.4×10−11J