Read the assertion and reason carefully to mark the correct option ou...
Strain is the ratio of change in dimensions of the body to the original dimensions. Because this is a ratio, therefore it is dimensionless quantity.
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Read the assertion and reason carefully to mark the correct option ou...
Assertion: Strain is a unitless quantity.
Reason: Strain is equivalent to force.
The correct answer to this question is option C, which states that the assertion is true but the reason is false.
Explanation:
Strain:
Strain is defined as the measure of deformation or elongation of a material per unit length. It is a dimensionless quantity because it is the ratio of the change in length (deformation) to the original length of the material. Since both the numerator and denominator of this ratio have the same unit, they cancel out, resulting in a unitless quantity.
Unit of Strain:
The unit of strain is therefore not equivalent to force, as stated in the reason. Force is measured in units such as Newtons (N), while strain is measured in units such as meters per meter (m/m) or millimeters per millimeter (mm/mm), which are unitless.
Example:
For example, if a material has an original length of 1 meter and it elongates by 0.1 meters, the strain would be 0.1/1 = 0.1. This means that the material has experienced a strain of 0.1, which is a unitless quantity.
Conclusion:
In conclusion, the assertion that strain is a unitless quantity is true because it is a ratio of two lengths or deformations. However, the reason that strain is equivalent to force is false because strain is not measured in units of force. Hence, option C is the correct answer.
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