Question

Two resistors of resistances $R_{1} = (300 \pm 3)\Omega$and $R_{2} = (500 \pm 4)\Omega$are connected in series. The equivalent resistance of the series combination is

• A. $(800 \pm 1)\Omega$
• B. $(800 \pm 7)\Omega$
• C. $(200 \pm 7)\Omega$
• D. $(200 \pm 1)\Omega$

Answer 1

Answer: (B)

$(800 \pm 7)\Omega$

Answer 2

The equivalent resistances of series combinations is $R_{s} = R_{1} + R_{2} = 300\Omega + 500\Omega = 800\Omega$The error in equivalent resistances is given by

$\Delta R = (\Delta R_{1} + \Delta R_{2}) = (3 + 4)\Omega = 7\Omega$

Hence, the equivalent resistances along with error is $(800 \pm 7)\Omega.$