PQ is a tangent drawn from a point P to a circle with center O and QOR is a diameter of the circle such that ∠POR =120∘, then ∠OPQ is 30∘.
60°
Given that ∠POR=120∘
We know that ∠OQP is 90∘
Using external angle theorem, ∠POR=∠OQP+∠OPQ
⇒120∘=90∘+∠OPQ
⇒∠OPQ=120∘–90∘
⇒∠OPQ=30∘