![[APP1_U5-3_Centripetal_Acceleration_Sample_Problem_Car_on_Hill_and_Valley.png]] ### Top of the hill ### The Valley $\vec{F}_{net} = ma_c$ $F_g = ma_c$ $F_g = m \cdot \frac{v^2}{r}$ $\cancel {m} \cdot g = \cancel {m} \cdot \frac{v^2}{r}$ $\boxed {g = \frac{v^2}{r}}$ $\vec{F}_{net} = ma_c$ $F_N - F_g = m \cdot \frac{v^2}{r}$ $F_N = m \cdot \frac{v^2}{r} + F_g $ $F_N = m \cdot g + m \cdot g $ $F_N = 2 \cdot m \cdot g $ $F_N = 2 \cdot 60.0 kg \cdot 10 \frac{m}{s^2} $ $\boxed {F_N = 1200 N}$