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!

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TopNewestsince a(alpha) = dw/dt = (dw/ds )

(ds/dt)=w(dw/ds).Hence ans will be 3*4=12 – Piyush Bharti · 1 year, 6 months agoLog in to reply

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, 8 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, 5 months ago

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