Angular velocity of suspended rod

  • Thread starter Prathamesh
  • Start date
  • #1
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1

Homework Statement


A uniform rod of length L & mass m is suspended through an end. It is shifted through an angle of π/2 radian i.e. made horizontal and then released. Find angular velocity when rod is vertical.[/B]


Homework Equations




The Attempt at a Solution


My attempt to a problem is attached
with this post.

But

Solution says
By energy conservation law
1/2 I ω2= mg L/2
(ω = angular velocity)
Hence
ω=√ (3g/L)

Which one is correct? N why other is wrong?[/B]
 

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Answers and Replies

  • #2
but in your soln you have assumed that torque remains constant throughout which is wrong
You must correct it and integerate to get the right answer
 
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Likes Prathamesh and Sahil Dhull
  • #3
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1
Nope...i ve found the torque acting on the rod when it is in hzt position only.... and hence angular acceleration (alpha) also changes with theta...so by putting theta =π/2 i ve found w
 

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