Physics

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When switched off, a spinning ceiling fan slows down with an angular acceleration of 1.2 rad/s2. If the fan was spinning at the rate of 10π rad/sec before it was turned off, how many revolutions did it go through before coming to the stop?

• Physics -

φ=ω₀t-εt²/2
ω=ω₀-εt
ω=0
φ=2πN
0=ω₀-εt => t = ω₀/ε
2πN = ω₀t-εt²/2=
=ω₀²/ε - ε ω₀²/2ε²=ω₀²/2ε
N= ω₀²/4πε

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