\text{At $t_1=2.0 \mathrm{~s}$, the acceleration of a particle in counterclockwise circular motion is $(-6.0 \hat{i}-4.0 \hat{j}) \mathrm{m} / \mathrm{s}^2$.}

\text{ It moves at constant speed. At time $t_2=5.0 \mathrm{~s}$, the particle's acceleration is $(-4.0 \hat{i}+6.0 \hat{j}) \mathrm{m} / \mathrm{s}^2$.}

\text{ What is the radius of the path taken by the particle if $t_2-t_1$ is less than one period?}

A) 6.5 \text{m}\\ B) 2.9 \text{m}\\ C) 7.2 \text{m}\\ D) 1.6 \text{m}\\ E) .2 \text{m}\\

v=\frac{2\pi r}{T}=\frac{2 \pi \times8\times 10^6}{2.40 \times 3600}=5.8 \text{ m/s}

-\vec{m}_\text{eff}

\Rightarrow