I please Angular deceleration

AI Thread Summary
The discussion revolves around calculating the angular deceleration and initial angular speed of a circular saw blade that completes 1150 revolutions in 42 seconds while coasting to a stop. The user is seeking assistance with the equations of motion for rotational dynamics, specifically using the equations w = wo + at and w^2 = wo^2 + 2a(change in theta). A suggestion is made to incorporate an additional equation for angular displacement to facilitate solving for angular acceleration. The user expresses progress in understanding how to apply these equations after receiving guidance. The conversation emphasizes the importance of correctly applying rotational motion formulas to solve the problem.
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I need help please! Angular deceleration

Homework Statement



A circular saw blade completes 1150 revolutions in 42 s while coasting to a stop after being turned off. Assume constant deceleration.

(a) What is the angular deceleration? (rpm/s)

(b) What is the initial angular speed? (rpm)


Homework Equations



w=wo+at

w^2=wo^2+2a(change in theta)


The Attempt at a Solution


I tried to plug in one equation into the other but it did not work. Any help would be much appreciated.
 
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bob5445123 said:

Homework Statement



A circular saw blade completes 1150 revolutions in 42 s while coasting to a stop after being turned off. Assume constant deceleration.

(a) What is the angular deceleration? (rpm/s)

(b) What is the initial angular speed? (rpm)


Homework Equations



w=wo+at

w^2=wo^2+2a(change in theta)


The Attempt at a Solution


I tried to plug in one equation into the other but it did not work. Any help would be much appreciated.

Welcome to the PF.

There's one more relevant equation that you should add, and it will help you solve part (a). What is the equation for theta as a function of omega and angular acceleration?
 


berkeman said:
Welcome to the PF.

There's one more relevant equation that you should add, and it will help you solve part (a). What is the equation for theta as a function of omega and angular acceleration?

You mean theta=theta intial+wo(t)+1/2at^2?
 


Do you plug in the first equation into the theta equation and solve for a?
 


Alright I think i got it. Thanks for helping
 
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