Math Chapter Wise Length Of Curve, Surface Area And Volume Of Solids Of Revolution English MCQ UP PCS (Pre) 1995 Q.The value of the radius of curvature of the curve s = 4 a sin ψ ψ ψ at the (s, ψ ψ ψ) is– A4a cos B4a sec C1 sec 4 D1 cos 4a Show answer Correct answer: 4a cos