Solving Force and Inertia in Equation of Motion

AI Thread Summary
The discussion centers on the relationship between force, inertia, and motion in a system involving a piston and a flywheel. The equation of motion is established as F = ma and F = I(theta''), highlighting the connection between linear and angular dynamics. The force exerted by the piston changes over time, leading to the realization that torque (T) can be expressed as T = Ia, where 'a' represents angular acceleration. By calculating the resultant force acting along the tangential velocity of the flywheel and multiplying it by the radius, the angular acceleration can be derived using the equation Fr = Ia. The conversation confirms that standard linear equations can be adapted for rotational motion using the appropriate variables.
a.mlw.walker
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So I have a piston connected to a flywheel. If i push the piston with a force F, how does the equation of motion look? I'm not confident about putting inertias into the same equation as accelerations?

F = ma

F = I(theta'')

The force is changing with time.

EDIT:

So i have just realized that T = Ia, a is angular acceleration.

So if i find resultant force of piston acting along line of tangential velocity on the flywheel, then moultiply it by r of the flywheel,

Fr = Ia, then rearrange for a and i have angular acceleration of flywheel?
 
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Hi a.mlw.walker! :smile:

(have a tau: τ and a theta: θ and an omega: ω and an alpha: α :wink:)
a.mlw.walker said:
So i have just realized that T = Ia, a is angular acceleration.

So if i find resultant force of piston acting along line of tangential velocity on the flywheel, then moultiply it by r of the flywheel,

Fr = Ia, then rearrange for a and i have angular acceleration of flywheel?

That's right …

the standard linear equations apply, with τ I θ ω and α instead of F m s v and a. :wink:
 
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