A symmetrical double convex lens is cut into two equal parts by a plane containing the principal axis:

The power of the divided lens is:

equal to that of the original lens

The correct answer is Option (2) → equal to that of the original lens

When a symmetrical double convex lens is cut along a plane containing the principal axis, each half retains the same radii of curvature. The thickness decreases but the focal length depends mainly on the curvature of surfaces and refractive index, not on thickness for a thin lens.

Thus, the power of each half-lens remains the same as that of the original lens.

Final Answer: equal to that of the original lens