JEE Main & Advanced
Physics
Ray Optics
JEE PYQ-Ray Optics
question_answer
Diameter of a plano - convex lens is 6 cm and thickness at the centre is 3 mm. If speed of light in material of lens is\[2\times {{10}^{8}}m/s,\] the focal length of the lens is: [JEE MAIN 2013]