MCQ
$\pi $ mesons can be
- A${\pi ^ + }$ or ${\pi ^ - }$
- B${\pi ^ + }$ or ${\pi ^0}$
- C${\pi ^ - }$ or ${\pi ^0}$
- ✓${\pi ^ + },\;{\pi ^ - }$ or ${\pi ^0}$
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The whole arrangement is in air. The optical power of the system is .......$D$
Statement $(I)$: When an object is placed at the centre of curvature of a concave lens, image is formed at the centre of curvature of the lens on the other side.
Statement $(II)$: Concave lens always forms a virtual and erect image.
In the light of the above statements, choose the correct answer from the options given below: