Answer:
The time interval is
![t = 21.30 \ s](https://img.qammunity.org/2021/formulas/physics/college/mr9ghe2i6modh2ty57h6n7vjm0yiq9i0fx.png)
Step-by-step explanation:
From the question we are told that
The constant acceleration is
![\alpha = 0.029 \ rad / s^2](https://img.qammunity.org/2021/formulas/physics/college/sxdfc08mk211v2h6x3y7wnq3v0zly1lkjj.png)
The displacement is
According to the second equation of motion we have that
given that the blade started from rest
which is the initial angular velocity is 0
So
=>
![t = \sqrt{ (2 * \theta )/(\alpha ) }](https://img.qammunity.org/2021/formulas/physics/college/iie1cnatmphmm2s427pxc091zmap7ttvz0.png)
substituting values
=>
![t = \sqrt{ (2 * 6.58 )/(0.029 ) }](https://img.qammunity.org/2021/formulas/physics/college/8nstjugfbwj1rtsdtvd7pjnw27v6kogdsg.png)
=>
![t = 21.30 \ s](https://img.qammunity.org/2021/formulas/physics/college/mr9ghe2i6modh2ty57h6n7vjm0yiq9i0fx.png)