A bar of an alloy is loaded in tension at elevated temperature, so that time-dependent (creep) deformation occurs. Some creep data for this alloy at 200 C is given in the table:
Steady state creep rate (hr-1) stress (MPa)
2.5 x 10-3 55
2.4 x 10-2 69
Calculate the steady-state creep rate (in hr-1) if the bar has a tensile stress of (4.6x10^1) MPa at (2.45x10^2) oC. Assume that the activation energy for creep is 140 kJ/mol.