Question about kinematic equation

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The discussion centers on the derivation of the angular displacement equation in kinematics, specifically addressing the confusion surrounding the factor of 1/2 in the equation θ = (α)t²/2. The user correctly identifies that with an initial angular velocity (ω₀) of 0, the angular acceleration (α) relates to the final angular position (θ) through the average angular velocity. The average angular velocity is calculated as (ω₀ + ω_f)/2, leading to the conclusion that the factor of 1/2 accounts for the average over time.

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Assuming initial angular velocity is 0 I want to solve for final position theta

Ang Acceleration = Δw/Δt = w/t

w = Δ(theta)/Δt = theta/t

ang acc = theta/t^2

theta = (ang acc)(t^2)

but how come the kinematic equation is...theta = (ang acc)t^2/2

Where did my 2 go?
 
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Miike012 said:
Assuming initial angular velocity is 0 I want to solve for final position theta

Ang Acceleration = Δw/Δt = w/t

w = Δ(theta)/Δt = theta/t
this formula gives the average angular velocity. You are looking for the instantaneous final angular velocity, which is twice the average.
acc = theta/t^2

theta = (ang acc)(t^2)

but how come the kinematic equation is...theta = (ang acc)t^2/2

Where did my 2 go?
The displacement theta is {(wo+wf)/2} (t)
 

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