A fan blade, initially at rest, rotates with a constant acceleration of 0.029 rad/s2. What is the time interval required for it to reach a 6.58-rad displacement after starting from rest

Respuesta :

Answer:

The time interval is  [tex]t = 21.30 \ s[/tex]

Explanation:

From the question we are told that

    The constant acceleration is [tex]\alpha = 0.029 \ rad / s^2[/tex]

    The displacement is  [tex]\theta = 6.58 \ rad[/tex]

     

According to the second equation of motion we have that

    [tex]\theta = w_i* t + \frac{1}{2} * \alpha t^2[/tex]

given that the blade started from rest

     [tex]w_i[/tex] which is the initial angular velocity is 0

 So  

       [tex]\theta = 0 + \frac{1}{2} * \alpha t^2[/tex]

 =>  [tex]t = \sqrt{ \frac{2 * \theta }{\alpha } }[/tex]

substituting values  

=>    [tex]t = \sqrt{ \frac{2 * 6.58 }{0.029 } }[/tex]

=>    [tex]t = 21.30 \ s[/tex]