20 verified questions · ~22 minutes · answer key checked against the official NTA final key across multiple sources. Text-only questions (diagram-based excluded until they can be shown properly).
A finite size object is placed normal to the principal axis at a distance of 30 cm from a convex mirror of focal length 30 cm. A plane mirror is now placed in such a way that the image produced by both the mirrors coincide with each other. The distance between the two mirrors is:
Displacement of a wave is expressed as x(t) = 5 cos(628t + π/2) m. The wavelength of the wave when its velocity is 300 m/s is: (π = 3.14)
Answers are revealed after you attempt — that's what makes the diagnosis honest.