(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An airplane engine starts from rest; and 2 seconds later, it is rotating with an angular speed of 420 rev/min. If the angular acceleration is constant, how many reovlutions does the propeller undergo during this time?

2. Relevant equations

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

[tex]\alpha[/tex] = [tex]\Delta[/tex] [tex]\omega[/tex] / [tex]\Delta[/tex]

3. The attempt at a solution

I thought that if by converting rev/s to rad/s I could use the angular acceleration to somehow find the number of revolutions made in 2 seconds. But I'm not sure if this requires converting, or even if I am on the right track with the angular acceleration.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Rotational Kinematics? Revolutions of a propeller?

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