Question 659: Current Electricity

Question

Two metal wires of identical dimensions are connected in series. If $$\sigma $$1 and $$\sigma $$2 are the conductivity of the combination is

Accepted Answer

In figure, two metal wires of identical dimension are connected in series
$${R_{eq}} = {1 \over {{\sigma _1}A}} + {1 \over {{\sigma _2}A}} = {{{l_{eq}}} \over {{\sigma _{eq}}{A_{eq}}}}$$
$${{2l} \over {{\sigma _{eq}}A}} = {1 \over A}\left( {{{{\sigma _1} + {\sigma _2}} \over {{\sigma _1}{\sigma _2}}}} ight)$$
$$ 	herefore {\sigma _{eq}} = {{2{\sigma _1}{\sigma _2}} \over {{\sigma _1} + {\sigma _2}}}$$

Answer

$${{{\sigma _1} + {\sigma _2}} \over {{\sigma _1}{\sigma _2}}}$$

Answer

$${{{\sigma _1}{\sigma _2}} \over {{\sigma _1} + {\sigma _2}}}$$

Answer

$${{2{\sigma _1}{\sigma _2}} \over {{\sigma _1} + {\sigma _2}}}$$

Answer

$${{{\sigma _1} + {\sigma _2}} \over {2{\sigma _1}{\sigma _2}}}$$

Current Electricity

Two metal wires of identical dimensions are connected in series. If $\sigma 1 and \sigma $2 are the conductivity of the combination is

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