In this rotating frame, what are the "coordinate" fictitious forces? As before, suppose we choose to put only the second-order time derivatives on the right side of Newton's law: F + m r θ θ ˙ ˙ ′ 2 r ^ ^ − − m 2 r ˙ ˙ θ θ ˙ ˙ ′ θ θ ^ ^ + m ( 2 r Ω Ω θ θ ˙ ˙ ′ + r Ω Ω 2 ) r ^ ^ − − m ( 2 r ˙ ˙ Ω Ω ) θ θ ^ ^ = m r ¨ ¨ r ^ ^ + m r θ θ ¨ ¨ ′ θ θ ^ ^ = m a . ~ ~