Question

A copper rod of crosssectional area 0.500 cm2 and length 1.00 m is elongated by 2.00 * 10-2 mm and a steel rod of the same cross-sectional area but 0.100 m in length is elongated by 2.00 * 10-3 mm. Which rod is under greater tensile strain?

Answer 1

Answer:

They have the same tensile strain

Explanation:

Strain of a material is the ratio of its extension to its original length.

strain = e/lo

e is the extension

lo is the original length

For a copper rod;

e = 2.00 * 10^-2mm

lo = 1.00m

convert 1.00m to mm

1.00m = 1*10^-3mm

get the strain

Strain = 2.00 * 10^-2mm/1*10^-3mm

Strain = 2 * 10^{-2+3}

Strain = 2*10^1 = 20

For the steel

e = 2.00 * 10^-3mm

lo = 0.100m

convert 0.100m to mm

0.1m = 0.1*10^-3mm

0.1m = 10^-4mm

get the strain

Strain = 2.00 * 10^-3mm/10^-4mm

Strain = 2 * 10^{-3+4}

Strain = 2*10^1 = 20

Since the value of their strain are the same, this means that they a re under the SAME tensile strain. No one is greater that the other.