Question

The length of one rod $\ell_1=3.323 \,cm$ and the other is $\ell_2=3.321\, cm$. Both rods were measured with one measuring instrument with least count $0.001 \,cm$ Then $\left(\ell_1-\ell_2\right)$ is

• A. $(0.002 \pm 0.001) cm$
• B. $(0.002 \pm 0.000) cm$
• C. $(0.002 \pm 0.002) cm$
• D. None of these

Answer 1

Answer: (C)

$\ell_1-\ell_2=(3.323 \pm 0.001)-(3.321 \pm 0.001)$
$=(0.002 \pm 0.002) cm$