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JEE mechanics doubt!! plz help

Q. If angular velocity of a disc depends on angle rotated \(\theta\) as \(\omega\) =\(\theta^{2}\) +\(2\theta\), then its angular acceleration \(\alpha\) at \(\theta\)=1 rad is

(1) 8 rad/\(sec^{2}\)
(2) 10 rad/\(sec^{2}\)
(3) 12 rad/\(sec^{2}\)
(4) None of these
The answer is (3) but i am not getting a solution so someone please help by providing one. Thanks!

Note by Akhilesh Chobey
2 years, 4 months ago

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since a(alpha) = dw/dt = (dw/ds )(ds/dt)=w(dw/ds).Hence ans will be 3*4=12 Piyush Bharti · 1 year, 1 month ago

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i think angular acc is dw/dt to find that : first find dw/dtheta and then as we know w = dtheta/dt

so now take out inverse of w which is dt/dtheta and now divide dw/dtheta and dt/dtheta Vaibhav Chaturvedi · 1 year, 3 months ago

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First differentiate omega with respect to t to get the expression of alpha then put the value of omega at theta 1 and theta Vipra Goyal · 2 years ago

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