Q.

A thin uniform rod of length 2m, cross-sectional area 'A' and density 'd' is rotated about an axis passing through the centre and perpendicular to its length with angular velocity ω. If the value of ω in terms of its rotational kinetic energy E is αEAd then the value of α is ________ .             [2023]


Ans.

(3)

(KE)rotational=12Iω2=E

E=12ml212ω2 =12dAl312ω2

E=dA(2)324ω2

3EdA=ω  α=3