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In a concave lens, a ray of light emanating from the object parallel to the principal axis of the lens after refraction:

Asked in NEET 2026 · Lens formula and magnification

Answer: (2) appears to diverge from the first principal focus.

Step-by-step solution

A concave lens diverges a ray that arrives parallel to the principal axis.

Traced backwards, the refracted ray passes through the principal focus that lies on the same side of the lens as the incoming light.

Strictly, the point that parallel light appears to diverge from is the image-side (second) principal focus F₂, which for a diverging lens lies on the incident side.

Of the four options only (2) describes the ray correctly, that it appears to diverge from a principal focus on the incident side, so (2) is the answer; the booklet marks it (2*) for the same reason.

Why the other options are wrong

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