\(V \propto l\)
\(\mathrm{V}=\mathrm{k} l\)
Now, it is given \(\mathrm{E}=1.1\) \(volt\) for \(l_{1}=440\, \mathrm{cm}\) and \(V=0.5\) \(volt\) for \(l_{2}=220\, \mathrm{cm}\)
Let the error in reading of voltmeter be \(\Delta \mathrm{V}\) then, \(1.1=400\, \mathrm{K}\) and \((0.5-\Delta \mathrm{V})=220\, \mathrm{K}\)
\(\Rightarrow \frac{1.1}{440}=\frac{0.5-\Delta V}{220}\)
\(\therefore \) \(\Delta V=-0.05 \text { volt }\)
(લોખંડ અને કોપર-નિકલ મિશ્રધાતુના તારની અવરોધકતા અનુક્રમે $12 \;\mu \Omega {cm}$ અને $51\; \mu \Omega {cm}$ છે)