1 The proportional limit is a the stress at which the stress

1) The proportional limit is:

a) the stress at which the stress-strain curve is no longer linear.

b)measure of a material\'s stiffness

c)largest stress that a material can withstand without any measurable permanent strain.

d) a material\'s capacity to elongate without plastically deforming.

2) If the proportional limit for a material is measured to be 93 ksi while the corresponding normal strain is 0.0048 in./in., the modulus of elasticity, E of the material is ___________ ksi.

Solution

1) Opton D is correct. in proportional limit material elonagte without plastically deforming. If proportionality limit exceeds it will deform plastically.

2) E= 93/0.0048

=19375 ksi.