A wheel starts rotating at 10 rad/sec and attains the angular velocity of 100 rad/sec in 15 seconds. What is the angular acceleration in rad/sec2? A. 10 B. 110/15 C. 100/15 D. 6

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The Correct answer is (D)

The equation of rotational motion for constant angular acceleration is given by

ωf = ωi  + αt

⇒ α = \(\frac{\omega_f - \omega_i}{t}\)

Where, 

  • ωf = final angular velocity
  • ωi = initial angular velocity
  • α = angular acceleration
  • t = time taken to reach final angular velocity from initial angular velocity.

Given, 

Initial angular velocity, ωi = 10 rad/s

final angular velocity, ωf = 100 rad/s

Time taken, t = 15 sec

Using the equation of rotational motion, angular acceleration (α) of the wheel, is given by 

α = \(\frac{100-10}{15} = \frac{90}{15}\)

⇒ α = 6 rad/sec2


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