# Physics (Stress&Strain)

posted by
**Danny** on
.

The Ultimate strength of a round steel rod is 630.000MPa. If a factor of safety of 5.000 is required, what is the maximum permissible load for the rod if it has a diameter of 3.000cm?

ANS = kN (Round to 3 decimal places)

Safety = 5.000

Rod diameter = 3.000cm = 0.03m

Ultimate Strength

= 630.000MPa = 630000kPa

Allowable strength

= Ultimate strength/ Factor of safety

= 630000kPa/ 0.03m

= 21000000kPa

Load = Allowable strength * Area

Area = pi * d^2/ 4

= 21000000kPa * 3.1416 * 3^2/ 4

= 21000000kPa * 3.1416 * 9/ 4

= 593762400kPa/ 4

ANS = 148440.600kPa

Please check. Thank you.