$Cu \rightarrow Cu ^{2+}+2 e ^{-}$

At cathode

$2 Ag ^{+}+2 e ^{-} \rightarrow 2 Ag$

Cell reaction $\rightarrow Cu +2 Ag ^{+} \rightarrow Cu ^{2+}+2 Ag$

$E _{\text {cell }}= E _{\text {cell }}^{0}-\frac{0.06}{2} \log \frac{\left[ Cu ^{2+}\right]}{\left[ Ag ^{+}\right]^{2}}$

$0.43= E _{\text {cell }}^{0}-\frac{0.06}{2} \log \frac{(0.001)}{(0.01)^{2}}$

$E _{\text {ceil }}^{0}=0.46$

$E _{\text {cell }}^{0}= E _{ Ag ^{+} / Ag }^{0}- E _{ Cu ^{2+} / Cu }^{0}$

$0.46=0.80- E _{ Cu ^{2+} / Cu }^{0}$

$E _{ Cu ^{2+} / Cu }^{0}=0.34$ volt

$E _{ Cu ^{2+} / Cu }^{0}=34 \times 10^{-2}$