The measurements from ______ are taken for the spherical lenses according to sign conventions.

Question

Question

This question was previously asked in

RRB JE CBT I - (Held On: 2 June 2019 Shift 1)

Answer 1

The correct answer is Optical centre

Key Points

Optical centre is the point on the principal axis of a lens where light rays passing through it do not deviate.
In the context of spherical lenses, measurements are taken from the optical centre according to sign conventions.
Sign conventions help in determining the focal length, image distance, and object distance in lens formulas.
Using the optical centre as a reference point simplifies the calculation and application of lens formulas in optics.

Additional Information

Spherical lenses can be either convex or concave, each having different properties and applications.
The principal axis is an imaginary line passing through the optical centre and the centres of curvature of the lens surfaces.
Sign conventions for lenses typically follow the Cartesian coordinate system, where distances measured in the direction of the incoming light are positive and those measured against it are negative.
Understanding the optical centre and sign conventions is crucial in fields like photography, microscopy, and vision correction.