A point object is placed 20 cm left of a convex lens of focal length f = 5 cm (see the figure). The lens is made to oscillate with small amplitude A along the horizontal axis. The image of the object will also oscillate along the axis with.
amplitude A9, out of phase with the oscillations of the lens
1v+120=15
v=203cm
Δxi=+v2u2Δx0
Δxi=A9 out of phase with lens
Hence (A) is correct