1.

A wire of length L and cross section area A is kept on a horizontal surface and one of its end is fixed at point 0. A ball of mass m is tied to its other end and the system is rotated with angular velocity omega.Show that increase in its length. Delta l = (m omega ^(2) L ^(2))/(AY). Y is young’s modulus.

Answer» <html><body><p></p>Solution :<img src="https://d10lpgp6xz60nq.cloudfront.net/physics_images/KPK_AIO_PHY_XI_P2_C09_E02_040_S01.png" width="80%"/> <br/> By rotating the ball of <a href="https://interviewquestions.tuteehub.com/tag/mass-1088425" style="font-weight:bold;" target="_blank" title="Click to know more about MASS">MASS</a> m with angular speed <a href="https://interviewquestions.tuteehub.com/tag/w-729065" style="font-weight:bold;" target="_blank" title="Click to know more about W">W</a>, the pseudo centifugal force acting on it due to centripetal force <br/> `F = ( mv ^(2))/() = ( <a href="https://interviewquestions.tuteehub.com/tag/ml-548251" style="font-weight:bold;" target="_blank" title="Click to know more about ML">ML</a> ^(2) omega ^(2))/( <a href="https://interviewquestions.tuteehub.com/tag/l-535906" style="font-weight:bold;" target="_blank" title="Click to know more about L">L</a> )` <br/> `F = mL iomega^(2)` <br/> `therefore` ongitudinal stress `sigma = (F)/(A) = (mL omega ^(2))/(A) ` <br/> Let increase in length of rod `= Dela L` <br/> `therefore` strain `= (Delta L )/(L)` <br/> Young modulus `Y = ("stress")/("strain") = ( m Lomega ^(2))/(A) //(Delta L )/(L)`<br/> `therefore Delta L = (m L ^(2) omega ^(2))/(A.Y)`</body></html>


Discussion

No Comment Found

Related InterviewSolutions