From = 0 to = 100 mm, the bar’s height is 20 mm. From = 100 mm to = 200 mm, its height varies linearly from 20 to 40 mm. From = 200 mm to = 300 mm, its height is 40 mm. The flat bar’s thickness is...

From
= 0 to
= 100 mm, the bar’s height is 20 mm. From

= 100 mm to

= 200 mm, its height varies linearly from 20 to 40 mm. From

= 200 mm to

= 300 mm, its height is 40 mm. The flat bar’s thickness is 20 mm. The modulus of elasticity of the material is
E
= 70 GPa. If the bar is subjected to tensile axial forces
P
= 50 kN at its ends, what is its change in length?