Concave lens: image is always virtual and diminishedअवतल लेंस: प्रतिबिंब सदा आभासी व छोटा

NCERT Fig 9.17 (b) · interactive diagram

Parts and their functions

• Concave (diverging) lens (अवतल (अपसारी) लेंस) — Thicker at the edges. Focal length negative.
• Object AB (बिंब AB) — Here 30 cm from a lens of f = −15 cm (NCERT Exercise 11, drawn to scale).
• Parallel ray → appears to come from F₁ (समांतर किरण → F₁ से आती प्रतीत) — After refraction it diverges; extended back (dashed) it passes through F₁ on the object side.
• Ray through O → undeviated (O से किरण → बिना विचलन) — Passes straight through the optical centre.
• Image A′B′ (virtual) (प्रतिबिंब A′B′ (आभासी)) — v = −10 cm: same side as the object, between F₁ and O. Virtual, erect, diminished.

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 9.17 (b). Report a mistake