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?

The rod under greater tensile strain is ; Neither of them i.e. They both have the same tensile strain

Given data :

Cross sectional area of copper rod = 0.5 cm²

Length of copper rod  = 1.0 m  = 1 * 10³ mm

Elongation of copper rod ( Ec )  = 2.0 * 10⁻² mm

For Steel

Cross sectional area of steel = 0.5 cm²

Length of steel rod = 0.1 m  = 1 * 10² mm

Elongation of steel rod  ( Es )=  2.0 * 10⁻³ mm

Determine the Tensile strain of each rod

i) For copper rod

Tensile strain = Ec / Length of copper rod

                       = ( 2.0 * 10⁻² ) /  ( 1 * 10³ )

                       = 2.0 * 10⁻⁵

ii) For the steel rod

Tensile strain = Es / Length of steel rod

                       = ( 2.0 * 10⁻³ ) / ( 1 * 10² )

                        = 2.0 * 10⁻⁵

The Tensile strain for the copper rod and the steel rod is the same ( 2.0 * 10⁻⁵ ) This means that both rods are under the same tensile strain

Learn more : link

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.

unlike poles attract

so here is the information for current research:

-nrel's geothermal analysts, scientists, and engineers perform a full range of research from developing advanced methods of locating and accessing geothermal resources to exploring innovative technologies to extract and produce clean energy from the heat of the earth

and here is the information for the technology of geothermal energy:

-it's clean and sustainable

-resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the earth's surface, and down even deeper to the extremely high temperatures of molten rock called magma

-almost everywhere, the shallow ground or upper 10 feet of the earth's surface maintains a nearly constant temperature between 50° and 60°f (10° and 16°c)

-geothermal heat pumps can tap into this resource to heat and cool buildings

-a geothermal heat pump system consists of a heat pump, an air delivery system (ductwork), and a heat exchanger-a system of pipes buried in the shallow ground near the building

-in the winter, the heat pump removes heat from the heat exchanger and pumps it into the indoor air delivery system

-in the summer, the process is reversed, and the heat pump moves heat from the indoor air into the heat exchanger

-the heat removed from the indoor air during the summer can also be used to provide a free source of hot water