A Disc, Initially At Rest, Is Rotated About Its Axis With A Uniform Angular Acceleration. In The First Two Seconds, It Rotates Through An Angle θ. In The Next Two Seconds, The Disc Will Rotate Through An Angle

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Question

A disc, initially at rest, is rotated about its axis with a uniform angular acceleration. In the first two seconds, it rotates through an angle θ. In the next two seconds, the disc will rotate through an angle

Solution

Correct option is

 

 = initial angular speed and α is the angular acceleration, Since ω0 = 0, we have  

                             

                   

Therefore, change in angle = 8α – 2α = 6α, which is .

                                                                                      

SIMILAR QUESTIONS

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Q3

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Q4

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Q5

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Q6

 

A simple pendulum of length L and with a bob of mass M is oscillating in a plane about a vertical line between angular limits

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Q7

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Q8

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