Given, voltage V=(100±5)V Current I=(10±0.2)A According to Ohm's law, V=IR or R=V∕I Taking log of both sides, logR=logV−logI Differentiating, we get
∆R
R
=
∆V
V
−
∆I
I
For maximum error,
∆R
R
=
∆V
V
+
∆I
I
Multiplying both sides by 100 for taking percentage, we get