A student determines the resistivity of an unknown wire to be ( uncertainty)

PHYSICS · Single correct · A Level · Physics · Measurements and their errors · Measurements and their errors

Problem

A student determines the resistivity of an unknown wire to be

(5.0 \pm 1.0) \times 10^{-7}\,\Omega\cdot\text{m}

(

1\,\sigma

uncertainty). Using the candidate values below, which option lists ALL materials that cannot be ruled out at the

1\,\sigma

level? Material-Resistivity (

\Omega\cdot\text{m}

20\,^\circ\text{C}

) • Brass

6.0 \times 10^{-8}

• Manganin

4.4 \times 10^{-7}

• Constantan

4.9 \times 10^{-7}

• Nichrome

1.10 \times 10^{-6}

(a) Constantan only (b) Manganin and Constantan (c) Manganin only (d) Manganin, Constantan, and Nichrome