evaluate power transmitted by shafthow do you

Question

Evaluate power transmitted by shaft:

How do you evaluate power transmitted by shaft (P)?

Sol.: Consider force 'F' Newton's acting tangentially on shaft of radius 'R'. If the shaft because of this turning moment (F X R) starts rotating at N rotation per minute then.

Work supplied to shaft/sec = F. Distance moved/sec.

= F.2  .R.N/60 Nm/sec

or,                               

Power (P) = F.R.2  .N/60 Nm/sec or watt. But F.R = Max. Torque (T) in N-m

That is                                       P = 2  .N.T_max/60 watts