# Angular Acceleration (1 Viewer)

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#### petal5

The problem is:

The angular speed of a propellor on a boat increases with constant acceleration from 50 rev/min to 150rev/min in 2.5s.What is the angular acceleration of the propellor?

I'm not sure how to go about the problem.So far I've converted the 50rev/min and the 150rev/min to rad/s.Do I have to work out wf-wi and tf-ti or am I going about it wrong?
Thanks!

Last edited:

#### Doc Al

Mentor
petal5 said:
Do I have to work out wf-wi and tf-ti or am I going about it wrong?
Sounds like you are on the right track.

#### physics.guru

Kinematic equations can be applied to translational motion with constant acceleration. The same works in rotational dynamics. In fact, the equations for both types of motion share a common format with different variables. Given an initial and final angular speed during some time interval, what is the acceleration? If you're still unsure, ask yourself, "How would I solve if the variables were dimensionally linear?" Is there a similar rotational equivalent?

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