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
    ω₀=10π rad/s
    ε=1.2 rad/s²
    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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