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Rotational Motion question

2022 · Q128
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Rotational Motion question

2022 · Q128

NEETPhysicsRotational MotionMCQ+4 / −1

The angular speed of a fly wheel moving with uniform angular acceleration changes from 1200 rpm to 3120 rpm in 16 seconds. The angular acceleration in rad/s2 is

  1. A
    2π\piπ
  2. B
    4π\piπ
  3. C
    12π\piπ
  4. D
    104π\piπ
View written solutionFree

Correct answer: B

Angular acceleration $$\alpha = {{{\omega _f} - {\omega _i}} \over t}$$

$${\omega _f} = 3120 \times {{2\pi } \over {60}}$$ rad/s

$${\omega _i} =1200 \times {{2\pi } \over {60}}$$ rad/s

$$ \Rightarrow \alpha = {{(3120 - 1200)} \over {16}} \times {{2\pi } \over {60}} = 4\pi $$

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