Question

Angular velocity of minute hand of clock is positive or negative or zero

Answer 1

Angular velocity, ω⃗ ω→, and angular acceleration, α⃗ α→, are both vector quantities, The direction of the angular velocity vector is determined by the right-hand rule, as in the picture below.

The angular acceleration vector is

α⃗ =dω⃗ dt=limΔt→0ω⃗ (t+Δt)−ω⃗ (t))Δtα→=dω→dt=limΔt→0ω→(t+Δt)−ω→(t))Δt.