Since deflecting torque varies as (current)2, we have Td ∝ I2
For spring control, Tc ∝ θ
∴ θ ∝ I2
For gravity control, Tc ∝ sinθ
∴ sinθ ∝ I2
(i) For spring control 90º ∝ 52 and θ ∝ 32 ; θ = 90° × 32/52 = 32.4º
(ii) For gravity control sin 90º ∝ 52 and sinθ ∝ 32
sinθ = 9/25 = 0.36; θ = sin−1 (0.36) = 21.1º.