Getting the angular velocity using the angular acceleration graph

Thread starter dahoom102
Start date Feb 8, 2021
Tags

Acceleration Angels Angular Angular acceleration Angular velocity Graph Rotaional kinematics Velocity

AI Thread Summary

The discussion focuses on calculating angular velocity from an angular acceleration graph. The area under the graph was computed as -29, leading to the equation Δω = ωf - ωi, where ωi is 5. The resulting calculation gives ωf as 24, but this value does not match any provided options. A participant acknowledges a mistake in their calculations, indicating the importance of careful analysis in solving such problems. The conversation emphasizes the relevance of understanding the relationship between angular acceleration and angular velocity.

Feb 8, 2021

dahoom102

Homework Statement: The graph below shows a plot of angular acceleration in rad/s2 from t=0 to t = 8s, the angular velocity at t=0 is 5rad/s ccw. the angular velocity at t=8 is

Relevant Equations: α=dω/dθ

The answer here is A
What i did is getting the area as follows,
2×4×1/2 +3×-6×1/2 +4×-6 = -29
and then use this
Δω=ωf-ωi
-29=ωf-5
ωf=24
but there is no such choice.

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Feb 8, 2021

BvU

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Why 4x-6 (in your language) ?

Feb 8, 2021

dahoom102

BvU said:

Why 4x-6 (in your language) ?

oh my mistake I didn't notice thanks a lot!

Feb 8, 2021

kuruman

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dahoom102 said:

Relevant Equations:: α=dω/dθ

##\alpha = \dfrac{d\omega}{dt}=\omega \dfrac{d\omega}{d \theta} .~~## :oldsmile:

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