1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Calculate the power

  1. Jul 3, 2012 #1
    1. The problem statement, all variables and given/known data

    Calculate the power that can be safely transferred by a 100 mm shaft rotating at 150 revolutions per minute.

    2. Relevant equations

    Radius = diameter/2=100/2=50 mm
    Shaft from mild structural steel
    T= 320 N/mm2

    3. The attempt at a solution

    J=(3.14/2)*504= 1.57*6250000=9812500
    T=TJ/KY=320*9812500/6*50=3140000000/300=10466666.67 Nmm
    Changed to Nm= 10.466 Nm
    Per minute 150
    Per second = 150/60 = 2.5per second
    Angular velocity= 2.5 *(2*3.14)= 2.5*6.28=15.7 rad/sec
    Power=15.7*10.466=164.3162 Nm/sec= 164.3162 watts
    Power changed to horsepower= 220.35162 (hp) ????????????

    Please check my result:D
  2. jcsd
  3. Jul 4, 2012 #2
    can anyone help?
  4. Jul 4, 2012 #3
    I guess if the shaft is made of bamboo, less power transferred than if it is made of steel.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook