Formula for Critical Speed `text{rpm}` = `((4.76)(10^6)dF_s)/(Kl^2)` Enter Variables Minor diameter, `d` = in. Factor of safety, `K` = Unsupported length, `l` = in. End Fixity Factor, `F_s` = Fixed-free: 0.32 Supported-supported: 1.00 Fixed-supported: 1.55 Fixed-fixed: 2.24 Calculate View Result Critical Speed = rev./min. Copy Result