Calculate Angular Velocity ($\omega$): $\omega = 2\pi f = 2\pi(2) = 4\pi \text{ rad/s}$ [Source 43]

Forces at the Top: At the highest point of a vertical circle, both the Tension ($T$) and the Weight ($mg$) act downwards towards the center. The sum of these forces provides the necessary centripetal force ($F_c$). $T + mg = F_c = m\omega^2 r$ [Source 76, 82]

Calculate Centripetal Force: $F_c = 0.4 \times (4\pi)^2 \times 2$ $F_c = 0.8 \times 16\pi^2 = 12.8\pi^2$ Using $\pi^2 \approx 9.87$: $F_c \approx 12.8 \times 9.87 \approx 126.34 \text{ N}$

Calculate Tension: Rearranging the force equation for $T$: $T = m\omega^2 r - mg$ $T = 126.34 - (0.4 \times 9.8)$ $T = 126.34 - 3.92$ $T = 122.42 \text{ N}$ This matches Option 4.