Which of the following are correct?

Options

A. For a small deformation of a material, the ratio (stress/ strain) remains same.
B. For a large deformation of a material, the ratio (stress/ strain) decreases.
C. Two wires made of different materials, having the same diameter and length are connected end to end. A force is applied. This stretches their combined length by `2 mm`. Now, the strain is same in both the wire but stress is different.
D. None of these is correct.

Answer

A, B

Explanation

a. Within elastic limit Stress `=` Strain
b. Beyond elastic limit, a small increase in stress produces large deformation i.e, large strain So,
`("Stress")/("Strain")` decreases
c. Both the wires will have the same stress
Again`Y=("Stress")/("Strain")` of Strain `= ("Stress")/(Y)`
Since `Y` is different, strain will be different. So, option c is not correct.